Measure twice. Cut once.

Do the largest areas first. DON'T PANIC! When doing wings lay the sheet loose (do the bottom first) over the panel, tack once with the iron at the leading edge (just a 1/2" square spot) and then the trailing edge, then each corner, pulling the covering taught (just enough to get the wrinkles out before eadc tack). THEN start from the middle and work outwards.

When planning the covering think roof shingles. The overlaps should be away from exhaust oil flow and wind force. This is not super critical, but in the long run can make a difference. Once a piece flips up the airflow will work at it incessantly.

A squirt of Windex gives you the ability to poition covering pattern patches (and decals) and you can squeege out all the trapped air with a credit card or piece of thin plastic. Then iron the covering piece in place.

Keep your eye on the color. The coverings I've used darken a shade or two when they're heated properly and you get a visual aid. Test a piece of covering on a scrap piece of balse to git the feel for how much heat it takes (and how you can re-heat and remove).

Monokote has a video that covers the basics. Does your local club have a copy to loan from their library?