Slight errors add up fast when you're making multiple miter cuts. For optimum accuracy, first give your mitersaw a tune-up. Following the manufacturer's instructions, adjust the saw to produce dead-on 45° cuts at both settings. To make a mitered frame begin by cutting a 45° miter on one end of each frame piece about 4" longer than the final size. Now rotate the blade to cut the opposite 45° angle.Attach one of the miter cutoffs to a 1x2" piece of scrap roughly as long as the frame pieces to create a combination stopblock/hold-down, as shown at left. Clamp the stopblock to the mitersaw fence at a distance equal to the final length of the frame parts. Butt the mitered end of each part firmly against the mitered stopblock, and cut the second miter.—Henry Long, Benbrook, Texas