Bookcases are great for storing books, nick nacks, and papers. If you are building one of your own, measuring and the layout of the bookcase are incredibly important.
Step 1 - Cuff
Begin the bookcase by cuffing the 4' x 8' plywood, good side up, to size.
Step 2 - Rip
Rip (a cut with the grain) the plywood lengthwise into strips slightly less than 16" wide. By making your cuts 15 7/8" cuts instead of 16" cuts you can get three pieces from one 48" piece. Cut on the scrap side of the wood to allow for the width of the saw blade called a kerf (approximately 1/16"). For both accuracy and safety, keep your eyes on the fence, not the saw blade. The person "catching" the wood as it comes from the saw should support the wood only. Do not pull the wood or the cut will not be even.
Step 3 - Crosscut
Crosscut (a cut across the grain) plywood to length as specified in the plans. Making multiple cuts of identical size like those necessary for the shelves can be difficult. Using a miter gauge and the rip fence with a stop block as a measuring tool is a real time saver when making multiple cuts.