Affiliate Marketing Secrets

I’m interested in advertising and selling certain clothing/accessories that could greatly appeal to Japanese youth, but am currently based in the United States. I was wondering if anyone might have some tips or sort of “how-to” advice on the steps I might take to attempt a business venture on the Japanese market.
What would be an absolute must?
Would it be advisable to have an affiliate actually in the nation of prospect?
Would a website be the best way to start off?
If online, any advice on how one might provide savings on shipping for customers in Japan (assuming I remain based in the U.S.)?
I would greatly appreciate being pointed in the right direction for more information if you are unable to explain yourself. Any help is appreciated, thank you.