Disposing of unwanted paint can be difficult because paint is considered a hazardous waste that can leech into the ground when in liquid form. Here’s a tip for drying out paint to simplify disposal.
Stir sawdust or cat litter into the container until the paint is covered and let it sit until the mixture is dry. Depending on the regulations in your area you may be able to discard the dried paint with your household garbage. Check with your state environmental protection agency for specific guidelines in your area.