When painting small projects on a workbench, I place a few empty egg cartons upside-down under the workpiece. It lifts the project off of the top of the bench, making it easier to apply paint to nooks and crannies and along the sides of the project.
The egg cartons can be divided into smaller pieces, too, and you don’t have to worry about getting paint on them because they’re just egg cartons! — Nancy Luptowski
Egg cartons can also be used to hold small amounts of different colors of paint, for more colorful painting projects. The egg holders are perfect for holding just a little bit of paint, so you don’t have to keep your large paint containers open while you work.
It’s a good idea to keep a stash of three or four empty egg cartons with the rest of your painting supplies, so they’re available when you need them.