Nothing could be simpler, at least if you're building a straight longbow (requiring no bending form). I use 3/4" x 2"-wide osage boards with boo lam backing. Most boo loms come way too thick, and getting them thin and even is time-consuming but not rocket science. Use C-camps to glue backing to board, trace out your bow limb shape and start planing and rasping it down. Only problem I've found with boo backing is a tendency to string follow (as opposed to hickory backing), so best to shoot it a lot while tillering before getting down to final weight. Fun, easy, and makes slow but steady and reliable bows. I've done a couple dozen and am yet to have one break, while half my hick-backed bows eventually fail, so I have up on that. Have fun, dave