2. Know Your Sizing
Japanese sizing is by no means set to a regular standard. While most brands go by a standard size-up-1-from-your-usual, some follow their own rules (or traditional/heritage sizing). Brands like Engineered Garments sometimes base the sizing of a collection on how it best fits the designer. If you can get measurements of the item or a general description on how the item was made, it could help since you damn sure won't get to try it on.