Oy those things are annoying! If you can get plastic tweezers and pry them up from underneath, that's a good way. Helpful to have a piece of airline tubing with a siphon already running close by so that if you do pop them, you can try to catch all the cytoplasm and spores.
One thing I've been meaning to try but haven't gotten around to yet was to try a lasso to loop beneath them to pry them up gently.
Someone stop me! Please! But... not just yet...
55 Gal Tropical FW
55 Gal Mixed Reef