It couldn't be any easier! Just stick this tape to your bench and measure the full width of the item you whose center you need to locate, then find the same reading on the lower centering scale. That's it! No math, conversion of fractions, or writing down measurements on a scrap of lumber - just read the center location directly. The tape is marked with standard 1/16" graduations on the full scale, 1/8" graduations on the centering scale, as well as cumulative inch and foot markings and stud markings.