Saturate paper towels with water and squeeze out excess moisture.
Place the wet paper towels in a large jar, aquarium or shallow dish. The water in the paper towels will prevent earthworms from drying out as you collect them.
Sort through mulch and leaf beds to find any earthworms inside, and place them in your container.
Dig a hole in moist soil about 1 foot deep, with a 1-foot radius. Gently break up the soil, remove any earthworms you find and place them in your container. Continue digging holes and sorting through the soil until you gather all the earthworms you need.