Step 1: Remove old aerator from faucet spout (use pliers if needed).
Step 2: Turn water on to flush faucet
Step 3: Insert washer on to aerator.
Step 4: Screw aerator onto faucet spout.
Lester says: "Use masking tape to wrap the aerator if you need to use pliers to install your new aerator."
Step 5: Turn on water and check for leaks