Remove faucet handle
Place the rag in your sink in order to prevent any damage. Find out how the faucet handle is installed and start by unscrewing them with your screwdriver.
Remove retaining nut
Then unscrew retaining nut with a pipe wrench. The nut holds the faucet cartridge in and you want to loosen it before you can pull it out.
Remove the Old Cartridge
Pull the cartridge straight up in order to remove it. It is important to remember the position of the old cartridge because the new one has to be installed in the exact same way. If the cartridge is hard to get out you might need pliers to pull it out.
Install the New Cartridge
Push the new cartridge into its place, aligning it with the notches on the body of the faucet. Screw the retaining nut back on with a wrench. Be careful not to over-tighten. Then, screw the handles back on.