Best is one of the lighter Iron-on coverings such as Solarfilm, EXCEPT... avoid Towerkote and Econokote (same thing... different label) The wing gets part of its strength from the covering. Towerkote just doesn't have the strength.

Monokote and Ultrakote are OK... just a little heavy. The strongest and heaviest Monokote colors are the very pretty translucents. They can be beautiful looking on a plane like that one... but do add some un-necessary weight.

It will take nearly all of two 6 ft rolls of iron-on covering to do the plane if you plan the pieces out well. If you have excess waste you will need a 3rd roll. (its easy to have excess waste...)