Collect vegetation from your home woods and put it in a pot of water. Aromatic plants make the best cover scents because they'll infuse more oils and resin into the solution when cooked. This usually means evergreens like balsam fir, spruce, pine, and cedar, though you can use deciduous leaves or forbs like sassafras, sage, or goldenrod. If there aren't any strongly aromatic plants around, gather duff from the forest floor, and don't be afraid to throw in a little loose soil. You can also use fruits and nuts and make a solution that works as both a cover and an attractant.