lowes usually sells a 6" lip/bracket that you can bolt into 2x6's. I had a folding one initially and didn't like it very much, way too short and too difficult to get my bike onto the truck by myself. I bought two of the brackets and two 2x6x10's bolted the brackets on the end of the planks then used some 1x6's that I had lying around to anchor the two planks together, so now I've got a 12" wide ramp. After the wood dried out a bit I sanded it down and put some safety take on it, essentially like sandpaper tape, for better grip.