Go to Lowes, Ace hardware, or a plumbing supply and buy the delta brand repair kit. Make sure you replace the ball also and you have the right parts for your faucet. Shut off the hot and cold water to the faucet and take it apart. You may need the allen wrench included in the kit to remove the handle. When the allen screw is loose, the handle may need some upward persuasion to come off. The round chome piece should unscrew with the help of pliers. Use a clean soft rag around the teeth to avoid scratching the chrome. Lay out the new parts on the counter and watch closely how the old ball and parts came out. Clean it up with vineager and replace the parts and put it back to together with some teflon faucet grease. What out for those springs that can get lost easily. If all else fails, read the directions that comes with the kit. Forget the aftermarket brands, a good delta brand kit and ball should run about $15.