I am from the U.S., and I have moved to Canada once (2 years) and Japan four times (2 years, 3 months, 15 months, 15 months) before returning to the U.S. each time. In the process, I have learned a few tips and tricks for temporarily moving abroad, some of which are a little unique. I thought I would share these for anyone preparing for a similar move abroad, whether to Japan or anywhere else in the world. In some cases, you can purchase local equivalents once you've settled in (such as for personal hygiene products or stationery supplies) and in others, you may have some specialty supplies that you will want to bring with you for either the entirety of your time or that can be restocked when necessary (such as preferred hair or skin supplies, deodorant, etc...).
Personal Files: Bring original and/or photocopies (notarized if possible) of the following documents. Make sure you have digital files for everything listed here, and leave copies of essential files in a sealed envelope with a trusted point person in your home country, especially if you intend to return.
Photocopy of passport picture page and visa for yourself and any accompanying family members
Marriage license
Children's birth certificates
Death certificates, executor of estate documents, etc... for recently departed family members, if necessary
Photocopy of credit and debit cards, front and back, as well as licenses, school IDs, etc...
Paperwork for school or work affiliations
Lease and subleases, both for home country and new country
Prescriptions and descriptions of medications/medical conditions for yourself and any accompanying family members
Paperwork necessary for filing taxes, especially from abroad
Packing: Prioritize clothing that will cover the most number of seasons. If you anticipate not buying new clothing in your new country, presume that what you bring will get worn out. As such, bring nothing you would be heartbroken to throw away before returning home.
Shoes
Bring one pair of shoes for each season or type of use, especially if you anticipate having trouble finding appropriate sizes or fit in your new country (including slippers)
Those with particularly long, narrow or wide feet or arch concerns should research to see if buying shoes in the new country is possible and what the costs would be like.
Prioritize shoes that will work for multiple outfits or uses rather than specialty or fun shoes
Even if you plan to buy shoes while abroad, have the necessary shoes to get through your first month and any anticipated weather issues (rain, show, etc...)
Underwear & Socks
If you anticipate having trouble finding appropriate sizes, bring enough to cover a few weeks' time
Bring new packs lined up to replace pieces that get worn out
Lounge/Home wear
Especially in a place with thin insulation and expensive heating and cooling like Japan, have dedicated loungewear and layering pieces for at home
Bring a robe! I always forget and always regret it.
Jewelry
Bring pieces that are meaningful, but avoid anything overly bulky or valuable
Prioritize pieces that can be used for multiple outfits and uses.
Pajamas
These should cover most seasons
Bring fleeces suitable for sleeping
Bring one pair of fleece or flannel pajamas for cold weather (or more if the cold weather seasons are particularly extreme or lengthy)
Accessories
Scarves, gloves, hats, sunglasses etc...; soft accessories are useful for packing delicate items
Do not bring too many, though, as these should be easily acquired in your new country.
Jackets
Bring one jacket for each season or anticipated weather pattern, for a max of 3-4 (light, moderate, heavy, formal), with at least one being suitable for rain.
Formal/Work
If you are working in an office or need formal clothing for interviews or formal events, you will need a fair number of pieces.
If not, you should still bring at least one suit (black) and/or dress, ideally one that could work for any season.
Packing tools
Vacuum bags (with hand pump) and packing cubes are very convenient for making the most of packing space.
Make use of compressible items like socks, underwear, and accessories to stuff into bags or shoes or to line recesses in your suitcase to maximize all space.
Tools of the Trade: These are items that are essential to carrying out your work, research, or major hobbies. These will vary heavily from person to person, but these are mine.
Laptop
iPad and accessories
iPad cradle (for scanning)
Portable scanner
Electronic dictionary (Japanese)
External hard drive for backups
Thumb drives
Chargers and charging cables
Plug adapters/converters
Noise-cancelling Headphones
Stationery supplies: Mini ruler, pencil case, favorite pens and pencils, whiteout, erasers, pencil lead, journals, highlighters, sticky tabs (note: these can also be purchased in your new country, especially Japan)
Essential books and dictionaries (digitize before leaving, if possible)
Medications & Toiletries: To avoid potential legal complications, consult a consulate or embassy for your new country and/or read official policies from government websites concerning medications, including over the counter items. Many toiletries such as bandaids or bandages may be easily purchased in your new country, but bring enough for your first month or multiple sets if you have a strong brand preference.
Prescription Medication (potentially with yakkan shomei/approval from Customs)
For Japan, there are some medications that are legal but not locally available. These can be brought in hand luggage or potentially sent by mail, depending upon type and local regulations.
If it's a medication that is available in your new country, bring one month's supply to hold you over until you're able to find a local doctor and pharmacist.
If bringing contact lenses, check for permissible amount to bring in hand luggage
Over-the-Counter/General
Stomach and indigestion relief medications
Vitamins
Cold, Flu & Allergy medications (check legality, especially for cold medication)
Mild and moderate pain relievers
Medical Supplies
Bandaids
Bandage wraps (one large and one small; these can also be used for wrapping delicate items in your suitcase)
Braces/splints/slings (bring at least one appropriate brace or splint with you and potentially one backup for any current or recurring injuries)
Hot/Cold pack (these may or may not be easy to find in your new country)
Specialty hair products
Especially if your hair type or style is different from the majority of residents in your new country (particularly curly or textured hair)
You may want to bring your own hair dye, if you use it
Personal hygiene & daily life products
This includes items like tampons, menstrual pads, condoms, etc...
If you anticipate finding local replacements in your new country, bring only about a month's worth.
If you will be bringing multiple packages of items with you, remove items from their boxes and use as suitcase filler/padding. Bring one flattened box of each product in case questioned at Customs.
Preferred products
While it is better to find local equivalents when possible (especially for larger items like soap or shampoo), bring items you feel a strong brand loyalty to that could be difficult to replace, such as toothpaste, deodorant, makeup, or skin products.
Other: These are items I've discovered from personal experience are useful to have with you.
Fabric tape measurer
Used for taking body measurements for purchasing clothing and housing measurements for buying furniture
Luggage scale
For keeping track of suitcase weight as well as weighing books, presents, or other items to ship back home
Hand Towel
For the first day or two, until able to buy full size towels
Foodstuffs
Bring a few non-perishable snacks that won't require cooking in case you cannot find a restaurant or grocery store your first night
Check customs policies before bringing items like nuts, dried fruit, or jerky
Hobby materials
Find local products when possible, but have something on hand, especially if you need a few days to set up internet or television
Remove items from bulky packaging and store in sealable plastic bags
Reusable water bottle/coffee carafe
If bringing in carry-on, make sure it's empty
Packable cloth bag
Useful for additional materials you may pick up while traveling and can also be used for grocery shopping upon arrival (some places may charge for plastic bags).
Have at least 1 in your carryon and 1-2 more in your suitcase
Presents: Especially if moving to Japan, it is important to bring small items that are representative of your home town or state. These should be items that can be shown off or shared with others, and there should be a hierarchy of gifts depending upon who these are given to. Some ideas include:
Top level (main supervisor, principal, political figure)
Bottle of alcohol (especially scotch or whiskey; avoid name brands that are easy to find in Japan)
Handicraft from your area
Specialty food item from your area
Fancy pen
Monetary donation in lieu of gift (especially for a temple; use envelope)
Medium level (individuals with whom you will regularly work, people who are helpful as you settle in, people who can help make connections)
Picture book of your hometown/university
Mug or etched glass related to your hometown/university
Small bottle of maple syrup or other specialty food
Low level (small items that can serve as backup gifts or communal gifts for coworkers or fellow students)
Tin or box of cookies
Box of candies (avoid easily melted items like chocolate; maple sugar candies should be distributed immediately unless properly sealed)
Nicely packaged/specialty dried fruits or nuts
Things to Leave at Home:
Sheets, towels, cleaning supplies
Niche clothing items
For example, jackets or shoes that only work for a single situation or outfit
Unnecessary electronics
Leave hair dryers or cooking items at home unless you have a strong reason for taking them with you
Often it's better to buy items in the new country to make sure there are no plug or current issues
Bulky bags
Only bring bags or purses that can pack flat
If you must bring a bulky bag, stuff it with clothing to maintain its shape and then pack clothing around it
"Maybe" items
Anything that makes you think "maybe this would be useful" or "but what if I need it" should be left behind
If there is anyone willing to send you items over the course of your time away, leave them with a box of "maybe" items and replacements for essential clothing or toiletries as well as instructions for how and where to send them to you
Heavy books
Digitize if possible or check local libraries to see if you can access hard copies of the same texts while overseas
Illegal items
Items that are outlawed or heavily controlled in your new country should not be brought in, irrespective of rules in your home country
Ignorance of law will not necessarily protect you from prosecution and/or deportation.
Packing Tips:
Stuff the crevices
I typically start with socks, underwear, and under shirts that can be easily fit into recesses in my suitcase. After that, I move to larger clothing items
Shoe soles outward
Shoe soles can help provide stability and structure along the outer edge of the suitcase
Roll clothing
After folding as you normally would, roll your clothing into a narrow cylinder. This makes it easier to pack and compress as well as pull out specific items
Packing cubes
Packing cubes are useful for packing either by clothing category or day (especially if you want specific outfits together). Do not be afraid to pack them as full as they can go.
Soft-cover toiletry or jewelry kits.
Hard cases should only be used if they are completely and totally stuffed full (both to maximize space and also to prevent damage from items moving around)
Use clothing for padding
Use socks, bandages, scarves, fleeces, etc... for padding around delicate items, especially glass.
Cling wrap your bottles
Open any plastic bottles you are bringing and lay a piece of cling wrap over the opening before securing the lid. Wrap thoroughly with cling wrap and tape. Put in a plastic bag in case of puncture.
Stuff everything
Store jewelry or small items in shoes, toiletry bags, mugs, purses, etc...
Vacuum bags
These are most helpful for bulky items like winter coats and fleeces. Stash regular shirts and pants in packing cubs instead.
Strategize your overflow
Compare overweight costs versus bringing another suitcase versus shipping necessary items
Maximize your permitted carry-on/personal item allowance
Bring notably heavy items in your carryon if concerned about weight (if you gate check your carryon, be sure that your computer, wallet, jewelry, etc... are all in personal item)