You don't mention what brand of covering you bought, but most brands have an instruction sheet for first timers. Start with a small piece (such as the BOTTOM of an elevator) and then tackle the larger parts. Cover the bottom of the panel first, then the top. Same with the fuse...bottom, then sides, top last,with at least 1/8" overlap. Wing tips can be tricky, again...bottom wing panel first...then cover the top. Not unlike painting, make sure the piece is free of defects!
Covering is a lot like learning to fly, the more you do it...the better you get...good luck and have fun!