The choice of clothing depends on the period in which you will visit Tokyo. In general, advice that applies to all periods of the year, do not overload the suitcase: in Tokyo and in general all of Japan, hotels always have a laundromat that can be used to wash everything. In addition, the city offers continuous temptations and it's best to bring fewer things and pack lots of stuff upon to your return. Remember that the city is great and you will have to walk a lot so clothing and comfortable shoes are a must.