SPREAD THE WORD
livejournal, blogger, twitter, tumblr, WHATEVER. Talk about the game!
Facebook works if it's publicly visible on your wall but it's getting hard to link to facebook posts these days. Forums are okay if you're allowed to post this sort of thing there (don't annoy people by spamming, pls) and it's a forum that doesn't already have official topics. Posting about the game on the game's own forum doesn't count as spreading the word.

Post a link to the game page and say something about it. Post a screenshot. Talk about the characters. Whatever you like. You can even say you're just posting it to get a discount, that's fine.
Post something, then come here and post a link to whatever you posted so that I can see it, and I'll PM you a discount code.