[Tripsis]

I've got plans to go to Japan for 2 weeks around March to April, so it's not so warm then and the cherry blossoms should hopefully be blooming. So far all i've got done is my passport, next will be accomodation and plane tickets.

This will be my very first trip outside of Australia so i'm a bit nervy about preperations. Unfotunately it's my nature to be overcautious and i don't want to ruin the trip for myself because of it. So i wanted to know from those who have done the Japan trip themselves how much one should prepare beforehand and what can be left until I get there?
Heres a few examples i can think of:

Getting around Japan
Language barrier
Mobile/Cell phones, global roaming
Washing clothes


Any advice that can be offered will be greatly appreciated. Thanks.