The wing looks good, keep the pics coming! When you get to the point where you're ready to cover it, there are a couple things to remember.
First, it's a very lightweight structure and as you've seen it's easy to break. Once covered it gains a lot of strength. I assume you'll use SoLite (or similar) LIGHTWEIGHT covering and not a heavy Monokote type which will crush the airframe. Go very easy on shrinking the covering, and know that shrinking the covering can either add or remove twist to the wing. That is super common, especially on lightweight designs like the Dandy. Shrink the covering, check for warp, fix the warp, check for warp again, repeat until it's gone. After you do it a few times you'll get good at both building a flat wing and covering a wing that stays flat. It seems like my Switchback (essentially a low-wing Dandy) needed a little re-shrinking and un-twisting occasionally, but has been good for the past couple years.
Those ailerons are big and are also easy to warp with the covering, so go slowly. You'll see the covering start to pillow up as it tries to shrink over trapped air, so I'll often take a very tiny drill bit to add air holes in the structure. This allows the air to escape between ribs. An extra airhole drilled through the side, or where a hinge will go, also lets the air get out completely. Some ribs already have extra holes cut into them which does the same thing.
With all that said, assuming this is your first time covering a plane stick to the iron and don't bother with a heat gun. Don't expect it to be perfect and there WILL be wrinkles. Many can be shrunk out, but it takes practice. My suggestion is to make it look as decent as you have patience for, and know you can always come back and re-cover it later if you want. Don't over-do the heat! Too much can melt the covering, and if you use much heat near the edges the covering can come loose from the structure causing you to do it over.
