Draw a scale model of your desired knick-knack shelf plan on a piece of graph paper so that each graph paper square represents 1 inch. Depending on the sizes of individual pieces in your knick-knack collection, you may design the shelf so that all cubby holes are the same size or vary the sizes of the holes to showcase small and larger pieces. Keep larger holes toward the bottom of the shelf and in the center or evenly placed on each side to keep the shelf weight balanced.
Cut plywood pieces from the ½-inch thick plywood piece with the jigsaw to match the length of the shelf’s frame. Keep the width between 2 and 4 inches wide.
Attach the plywood pieces together to make a frame using finishing nails and wood glue.
Cut a ½-inch thick plywood piece with a width and height equal to the dimensions of the plywood frame. This is the shelf’s back piece. Attach the back piece to the frame using wood glue and finishing nails.
Cut ¼-inch thick plywood pieces to match the length of the horizontal and vertical lines in the shelf plan. Make the widths as wide as the shelf frame pieces. Do not cut sides for each individual cubby hole; instead, cut longer horizontal and vertical sections to fit your plan. You will cut notches to enable these pieces to intersect and form separate compartments.
Cut notches in the horizontal and vertical plywood pieces where you want the pieces to intersect. Make the notches half as long as the width of the plywood.
Lock the horizontal and vertical pieces together and reinforce their connections with wood glue to make compartments. Place the shelving system inside the frame to check how it fits and trim off excess wood if necessary.
Apply wood glue to the plywood shelf pieces where they touch the plywood frame or back piece. Place the shelving system inside the frame and place books over it to hold the plywood pieces down firmly until the glue dries.
Use a stud finder to find studs in the wall where you want to hang the shelf. Installing screws in studs rather than hollow drywall will give more stability. If you have a concrete nail, you can skip this process and install the shelf with masonry screws instead of wood screws.
Pre-drill two horizontal screw holes for every foot of shelf width. Use a level to ensure the screw holes are even.
Pre-drill holes in the back of the shelf so they correspond with the holes in the wall. Evenly distribute the holes along the width of the shelf to ensure even hanging and weight distribution.
Install the shelf to the wall, using screws and a screwdriver. You are now ready to add the knick knacks.