Collect as many acorns as you would like; the larger the better. Wash them and let dry. Bake in a 200 degree oven for a few hours to kill any bugs inside.
Choose your base color. Paint the bases of all the acorns, one side at a time, using the paintbrush. Set aside on a covered work surface and let dry.
Flip the acorns over and repeat. You may need two coats of paint depending on the color you chose. Let dry.
Paint the tops of the acorns; again, you may need a second coat. Let dry.
Seal all acorns with Satin Mod Podge and let dry. Add to a vase to display.
Video
Notes
My project was free - I already had the glass vase. If you need to get a glass vase, I recommend Dollar Tree.