I'm going to japan in march and I'm quite clueless on what to bring with me, any ideas?

How long are you going for? I try to not travel with anything larger than a carry-on and just do laundry in my sink every night but if you are staying in one place you don't need to worry about that. Basically, take a week's worth of clothing, plan on doing laundry and remember that whatever luggage you take you should be able to manage yourself. I would NOT take two of the biggest bags I could find plus a couple of carry-ons. How would you drag it around?