For the second coat, apply a light, streaky coat of the darker brown mixture, and while it's still wet, drag and rock the wood-graining tool through it to create the knots and grain naturally found in wood. Use the edges of the tool to create different looks. If an area looks a little too dark, lightly sweep a dry brush over the paint. For areas the wood-graining tool won't fit into, use the dry brush to create a strie effect. If you want more of a challenge, use the artist brushes to create additional wood effects.