Since you have not used your trimmer for some time, there is a good chance the battery or switch leads are corroded. Check out the troubleshooting page for more information.

To replace the trimmer blade simply remove the black and silver cap attached to the blue ring at the top of your trimmer (make sure you remove the battery first). Inside the cap is the blade. Carefully remove the blade and place your new trimmer blade in its place. For more information check out the troubleshooting page.

There is a good chance that some debris got caught up inside top and is blocking the hole that allows water to pass through it. Use a toothpick or similar thin tool to dislodge and remove the debris. Be sure to check out the troubleshooting page for more help.