[Gundam, you could use advice in more fashion areas than just formalwear, dear lord...]

Alright. Stick to dark, neutral colors for the suit itself. Black is always going to be your safest bet, but I think you could actually pull navy off pretty well if you'd rather go that route. Personally, I'd go for a full three piece suit since balls are supposed to be pretty formal, right? [He's...never been to one either so...] But that's just me. Regardless of whether you decide to do the same or not, control your obvious need for ridiculous patterns. That goes for both vests and ties. Just go with solid colors or a simple, subtle pattern and make sure everything matches. Oh, and black dress shoes and socks.

[There you go, there's a little advice. Free of charge, even!]