Do a search. It will turn up more answers than just starting a new post.
There were at least a few good ones in the past week or two alone.
Look for things like "fender chop", "TJ flare", you get the idea. A couple had links to other sites for even more info.
Position the flare were you want it, use nail polish to mark the holes to drill. Have someone else hold the flare of course, but that's how I did it, and all the flares came out perfectly even.