Before you sell or give away your iPod touch, see the Apple Support article What to do before selling or giving away your iPhone, iPad, or iPod touch, and be sure to perform the following tasks:
Back up iPod touch with iCloud backup or back up iPod touch with iTunes. If you replace one iPod touch with another, you can use the setup assistant to restore the backup to your new iPod touch.
Erase all content and settings, which includes your personal information.