Shut off your water at the main source by locating the main water line and turning the valve that regulates the water flow. If you have newer plumbing attached to your faucet, then you may have a shut-off valve directly underneath the faucet assembly, which makes it easier.
Place a rag or other type of drain stopper in the drain under the faucet you're working on so you don't lose any parts. Set all the parts down in a line when you remove them, so you remember the correct order when putting pieces back together.
Use a flat head screwdriver to pry off the plastic end caps on each of the handles of the faucet and set them aside.
Find the screw that is located in the center of each of the handles and remove the screws using a Phillips screwdriver.
Remove the faucet handles one at a time by twisting them around until they slide off. In many cases, especially with handles that don't turn easily, you may need to wrap a rag around the outside of each of the handles and use a wrench to remove them. Be careful not to scratch the surface of the handles.
Once each of the faucet handles has been removed, lather the inner threads of the handle stems with plumber's grease. Be sure you have a thorough coat of plumber's grease on each of the stems, because this is normally the cause of faucets that do not turn easily. Do not use petroleum jelly because it has a tendency to wear off with time. Plumber's grease, or silicone grease, is the best option when greasing the handle stems.
Attach both handles back to their respective stems, reinstall the screws, put the plastic caps back on, and turn the water back on. The handles on your faucet should now turn easier.