Brackets are available in a myriad of shapes and sizes. Using brackets to support and create a shelf allows the shelf to be coordinated with the room decor, be custom-sized, and be built by an intermediately skilled home decor DIY-er. Several shelves, staggered on a wall, make a serious design statement. A shelf placed above a door is a found-space storage solution, and a series of shelves running around a room's perimeter, high on a wall, can make a lateral book case for a small library.
Choose brackets that will accommodate the chosen shelf. A typical shelf is 12 inches deep. This is the measurement from the front of the shelf to the wall. Brackets are basically "L" -shaped; one leg of the L is attached to the wall, the other leg, which protrudes from the wall at a 90-degree angle, supports the shelf. The length of the protruding leg must be at least two-thirds of the depth of the shelf. For example, if the desired shelf is 12 inches deep, the supporting legs of the bracket must be at least 8 inches. Usually, both legs of the brackets are the same length; but this is not a hard rule.
Choose the number of brackets to use for the shelf. If the brackets are spaced too far apart, the shelf will sag. A good rule of thumb is to place a bracket every 16 inches. Place one at each end of the shelf, 1 inch from the outside edge, and every 16 inches along the shelf length.
Mark the wall, with the self-erasing marker, at the position of the underside of the shelf. Measure the distance from the floor to this mark. The 90-degree angle of the bracket will be aligned with this mark. The shelf will sit on the legs of the brackets that protrude from the wall at this mark. Mark the wall, measuring up from the floor, at 16-inch increments, one location marker for each bracket and one mark for each of the end brackets.
Install the brackets onto the wall at the indicated bracket locations, following the manufacturer's directions for attaching the brackets to the wall.
Place the shelf, centered, on top of the brackets and insert screws up through the brackets into the bottom of the shelf to secure it into position. It is helpful to pre-drill the screw holes to prevent a wood shelf from splitting.