First, do a search and read all you can on the subject. Then setup your flags and chart what wind does what on the target. Wind on different days, or different relays will influence your shot, sometimes a 9 o'clock wind does this, and sometimes it does that. Shoot sighters and be sure of your group center in a certain condition. Just because you shoot one sighter that results in an X does not mean your group center is in that location, and following shots can be sub-par.
Another thing to remember is, it is not 'plug and play'. If you have 5 flags in a 50 yard spread, you still don't have much data to go by. Two flags sitting 3-4 feet apart can read totally different and therein lies the problem, all that empty space with no flags.
More flags is better, unless each is doing it's own thing and you can't pick out which one is the 'key'.
I like to stagger my flags so I am looking down a tunnel.
It takes time to get a feel for what they are telling you, and no quick and easy answer is available.