I frequently use small amounts of paint from cans, but I don’t like to see paint go to waste because it has hardened around the rim, run over the edge of the can or thickened from air exposure. To avoid waste, I punch a hole near the edge of the can’s lid with an awl. Then I turn the can over and squeeze until I’ve got as much paint as I need. To seal the can, I just insert and tighten a sheet-metal screw in the hole. When I’m ready for more paint, I remove the screw and squeeze out what I need.