Just wanted to share some research on a couple of ways to cover Greenhouse Domes. I'll update
The easy/quick way: get cheap greenhouse plastic and cut it to fit/overlap, & tape it with waterproof tape.
Another solution is to shrink wrap your dome with industrial/marine shrink wrap. This shrink wrap comes in larges sizes, & you can use a propane torch to heat-shrink it on. These guys on youtube show the process:
Another solution is polycarb panels. It takes quite a bit more work and money, but the panels will help insulate, and last much longer. Check out this video to see how its done: