Agreed... get a manual. Sometimes you can find Clymer service manuals on ebay for 20-30bux. $75 is worth it if you are opening up your bottom end for the first time. I just split my first cases recently and I was very glad to have the manual there. Very helpful.
You'll need a case splitter to do the job properly. Trust me, you'll want it so you aren't tempted to get the screw driver out and pry it apart. You can get specialized moto ones from on-line moto retailers or go to harbor freight for a generic splitter.
What to look out for? I'm a rookie but I can tell you right now, you'll want to keep everything in order and do it slowly. There are a lot of parts in and around hte cases. Easy to mess it up.