Don't spend a lot of time getting the covering to look great. I know you probably have great pride in your work, and you want it to look fantastic at the club and all, but really, it's just a trainer, and it's more important that you are relaxed flying it.

My recommendation for a first kit: Cover the entire model with the same color (monokote or Ultracote, doesn't matter, whatever's cheaper). Then you don't have to worry about seams. Just concentrate on making sure everything is covered. Then, use self-adhesive trim strips to put enough pattern on the bottom of the wing so you can tell the top from the bottom way out in the air. On my pizza-box flyer, I just put two big "O" on the bottom, and they were really easy to see. A big checkerboard would would work as well. Don't worry about bubbles. Go fly.