When your iPod or iPod Touch goes through the washer, you can't do much to repair it on your own. Apple's optional AppleCare+ coverage includes accidental water damage, so if you purchased AppleCare+, take the iPod to Apple. If not, follow a few troubleshooting steps that may return your iPod to good health. Don't turn on the iPod or charge it during the process to prevent irreversible damage.
Dry the iPod
Dry the iPod as much as possible. Remove any cables and the case, if it has one. Don't shake it to get the water out, but position it on a towel where water can run out of the ports. Do not apply heat of any kind. When the iPod is dry on the exterior, submerge it in a container of dry rice, which acts as a desiccant. Completely cover the iPod with rice and cover the container. Wait 48 hours before removing your iPod from the rice. Charge the unit briefly using the wall charger and then see if the iPod will turn on. If not, or if it behaves erratically, turn it off and take it to an authorized Apple service technician.