- Launch Settings from your Home screen.
- Tap Mail, Contacts, Calendars.
- Tap Add Account...
- Tap Gmail.
- Enter your name, Gmail email address, password, and a descriptive name (like Gmail, or Personal, so you can identify it later).
- Select which services you want to leave on for sync, Mail, Calendars, and Notes. (You probably want all of them on.)
- Tap Save.