Nail Gradation Sponge used to generate gradient nails. (Handle Included). The way to Use: In the sale that you want the gradation to be visible on your nails, paint your sponge with all of the polishes. Ensure that the colors overlap slightly. Dab the sponge lightly onto your nail for repeatedly. While dabbing, use a really slight up and down motion in order to blend the colours together. Work with a cotton swab dipped in nail polish remover to straighten out the mess. Squeeze in a layer of your top coat.