As a final check when taping drywall joints, use a side light to check for smoothness. The light can be a halogen worklight, a troublelight, a lamp without a shade, even a larger flashlight. Hold the light close to the wall next to the joints in several places to reveal high and low spots, or bumps and depressions, that otherwise would be easily missed.
To take measurements inside an area like a cabinet drawer, use your measuring tape from inside edge to inside edge. Take the reading and then add on the length of the tape housing which is often stamped on the case. Another way is to use your tape along with a combination square. Position the square upside down in one corner and pull the case past the square’s blade. Select a number on the blade, and add the length of the tape.