From a Home screen, navigate: Apps > Settings > Accounts (Personal section).
Tap Add account.
Enter the Gmail address then tap NEXT (located in the lower-right).
Enter the password then tap NEXT.
If presented, configure the following as desired then tap NEXT:
Enabled when a check mark is present.
Back up your device's apps, app data, settings and Wi-Fi passwords
Keep me up to date with news and offers from Google Play
If presented to Set up payment info, select any of the following then tap CONTINUE (located in the lower-right):
Add credit or debit card
If applicable, complete all remaining steps to set up payment info.