Shelves that are hung without brackets are seamless and attractive, looking as though they are floating on the wall. Paying a professional to install shelves without brackets is expensive, however, simple bracketless shelves can be made cheaply by anyone with a circular saw. The shelves are made of 1x2 lumber pressed between two plywood boards. One side of the 1x2 frame is left open so that it can rest on a 2x2 wood support that is secured to the wall.
Plan the location of every shelf, and make note of the measurements. Use a level to make straight lines with tape or a pencil.
Cut two ½-inch plywood boards to the size needed. Cut one 1x2 to match the length, and two more to match the width or depth of the board.
Build a U-shaped frame with the 1x2s, 2-inch side out, using glue to bond the corners and two nails per corner to fasten them together. Use a razor to remove any glue that escapes. This should look like a rectangle that is missing one long side.
Affix both boards from step 2 to the top and bottom of the frame from step 3. Apply wood glue to both sides and attach the boards to the frame, then clamp the wood together for 24-hours so the glue may dry. Insert a nail every three inches to secure to boards to the frame.
Repeat steps 2 through 4 until all of the shelves are made.
Cut the 2x2s to the length of the shelves, cutting as many needed for the number of shelves.
Use an electronic stud finder to locate the studs in the wall that intersect with the straight lines from step one. Put the 2x2 even with the line, then drill a 3-inch screw through the 2x2, through the wall and into the stud.
Mount the open end of the shelf on the 2x2. Add nails every 2-inches through the plywood and into the 2x2 to secure the shelf. Hammer in 2-inch nails through the 1x2 and into the 2x2 for extra support.