Do alot of research.
Dont get caught up in buying .biz .ws or org. May want to consider .info for some but its going to be a crap shoot.
Stick with .net and .com (unless your .tv

who already has a strong hold on that domain)
Learn how to use Bido, online translators, IE8's translation application, googles keyword tool, search volume tools and keep up on idn.idn
RD has the market on China its been his baby for along time. Chinease and Japanese are very hard languages to understand there are so many variables. Make sure you have a good translation before you buy.
Never sell on ebay. You will be sterotyped.
Keep track on the forums. There are really only a few. Read everything from day one.
Have some money to waste, because your going to reg some crap domains. Its just the way it is.
Dont expect to sell alot yet. Its not happening. Cant even sell the ascii right now at what they are really worth.
Dont let someone tell you idn's are not going to happen. Its already in the works, and getting closer and closer. There is already alot, I mean alot, of $$ into making this happen.
Its simmilar to when 3 letter .coms were going for 50 bucks many years back. I still remember people saying they had no value.
Watch for drops. Its the best way to nab. If you watch you will see some months drop alot and some dont drop at all. I will leave that up to you to find out what months are best.
Good luck with them all. Its a good bet that you could come out way ahead in a few years if you learn the best techniques. There are alot of people out here willing to help.