Its hot down here!
Pack light!And pref a comfortable backpack or small suitcase with wheels. Pack alot of light t-shirts and light tops,in the 'Winter' which is Dec-Feb the temperature only get's down to about 16 at the lowest so no heavy jackets required.In the Summer you will sweat alot so do pack many tops and shorts,comfortable sandals.They sell flipflops everywhere for 300 yen but keep in mind the largest shoe size is 25 cm. Bring what you require as all toiletries/Medicines are in Japanese,Also bring your own condoms as they do only sell Japanese size.Def bring your own toothpaste,Japanese toothpaste is awful and the import stuff is expensive.Wet wipes,tissues and make up are all cheap in Japan.Don't forget deodarant,Japanese deodarant does not work! This is Japan so photo equipment is readily available but keep in mind everything is written in Japanese.