If you're going for an actual replica - not a representation in tube and gusset construction - you're thinking the wrong way in skills required.
You'll be far better suited taking a wood working class and becoming friends with carpenters and cabinet makers than delving into calculus and drinking coffee with guys from NASA.
At any rate, your question is sort of loaded since we don't know your background. For your average farmboy there isn't anything too daunting in the skills to pick up, since he's been around most of them all his life - but if someone were a city type that never drove a nail to so much as hang a picture there's a lot of basic stuff to pick up.
The mantra is as old as history itself - find someone who knows and can teach. Learn from them.
Best thing to do is build a rudder. Most of the skills required for the rest of the build will present themselves in a rudder build, and it's one of the least expensive parts to put together.
I'd also serious recommend you look into a tube-and-gusset build for your first plane. It's the least expensive and requires the fewest specialized skills of all types. Airdrome Airplanes has a fantastic set of offerings at super great prices (and loads of support).