All roleplaying really needs is a bit of thought. Generally using the 5 Ws works. (Who, what, where, when, why) If you suck at memorizing stuff, you can write it down and tape it to your monitor or something.
And about acronyms and stuff: Nobody's really found out how to say you'll 'be right back' in character, so you might as well do it ((in double parentheses- fear my horrid spelling.))
In my opinion, all RP really takes is thinking about what you're doing, and forgetting it's all just a game. This is easy for some people (like me, even though I only lightly roleplay). And, if you don't feel like spending a ton of time making up background history, you can RolePlay Lite(TM) and not worry about as much.