Use L brackets (sometimes called angle irons) to install a board mounted valance above a window. Board mounted window treatments use L brackets to attach the board to the wall. The L brackets or angle irons are usually installed a few inches above the window frame. Use a stud finder on the wall to find and mark studs, so that the brackets can be installed on top of the studs, allowing the screws to screw into the wood behind the wall’s sheet rock. Attaching the L bracket on top of a stud allows the board mounted valance to be more securely mounted to the wall. Make sure that the L bracket size is less than the board width. (A 1″ x 4″ piece of wood will use a 3″ angle iron bracket.) Since you will not know where the studs are located until you begin installing the valance, pre-drilling holes (as stated on the video) in the mounting board is not necessary. The screws used to attach the L brackets to the mounting board are short (3/4″) and normally do not split most new softer wood. When attaching the L brackets to the wall, longer screws should be used. The screws should be long enough to penetrate 1/2″ or thicker sheet rock and have enough depth left to penetrate about 3/4″ into the stud behind the wall. Be very careful to check walls for the location of water pipes, vent pipes, air conditioning lines, electrical lines, or other problems before attaching anything to the wall.