Sink faucets and tub faucets use a variety of set screws to secure faucet handles and spouts. The key to set screw removal for a faucet repair is locating the set screw. Some set screws are hidden behind cover plates. Others are located in obscure places where you would not normally look. Most set screws are small--always close the bathtub or sink drain while removing the set screw to prevent accidentally dropping it down the drain.
Look for a screw or rubber plug under the bend of lever faucets. The rubber plug cover pulls off to reveal the screw head. Turn the set screw counterclockwise with an Allen wrench or Phillips head screwdriver to remove the screw from the handle.
Find the seam between the front of the lever knob and the side of the knob, if you don't see the set screw under the curve. Insert a small flat head screwdriver between the seam to pop off the small oval cover. The set screw is below the cover. Remove the screw with the appropriate Allen wrench or screwdriver.
Pop the top cover off knob type faucet handles with a flat head screwdriver. Remove the plastic cover to reveal the set screw underneath.
Feel under the bottom edge of the escutcheon plate for a small set screw. The escutcheon plate is the large cover plate behind the faucet handles on bathtubs and showers. Some manufacturers place a set screw on the bottom or side edge of the escutcheon plate to secure the plate to a mount behind it. These are normally very small Allen head screws that can be removed with an Allen wrench.
Look under bathtub spouts for a set screw securing the spout. If the spout has a set screw, it will be close to the wall. Remove the set screw with a Phillips head screwdriver or Allen wrench.