For example the Links at the bottom of Math3w's posts which guide you thru the steps to have BB7.5...and I think it takes you all the way thru to over clocking
Read which ever guide you chose thru a couple of time and make sure that you understand the steps...If there is something that makes NO SENSE get some clarification before you start. Some steps you will not really get until your actually in the step. Get your droid and PC/Mac ready by having the necessary apps and files all ready to go. Then go slow...and follow each step to a T.
But if the idea of rooting and loading a custom ROM scares the hell out of you it is probably not a good Idea to try it.