Cover the mushroom cap with a bowl or cup, then leave it out for a few hours or overnight. When you take the cup off and remove the mushroom, there should be a colored print of spores left on the paper. This is your spore print. Sometimes, it might be helpful to use both black and white paper, putting the mushroom half over each color, if the. Spore prints are sent in a larger ziplock bag with "Microscopy use only" written on the ziplock. Spore prints will be labelled with an acronym for the variety or with the full variety name or, if it is a single print, the ziplock may be labelled. Be sure to check the homepage for relevant announcements!.