If the gasket is in good condition, you can just clean it up, give it a quick wipe with some isopropyl alcohol, and reuse it. Unfortunately, if it's in good shape, that means it's going to be really hard to get it off the cylinder head, and the chances of nicking or damaging the seal go up.

I would try finding something that won't gouge the head, and pry underneath the gasket at one corner. Once you get the seal broken, it should be pretty easy to lift up the rest of the cover. Also, be careful you don't bend or warp the cover as you're trying to wedge off the gasket.