From the Start screen, swipe left to display the apps list.
Alternatively, tap All apps icon (located in the lower-right, may require scrolling).
Navigate: Settings > email+accounts > add an account.
Select one of the following account types:
Additional account types (other than those listed below) appear, but are not POP/IMAP related.
This option may appear as "Microsoft account" if the primary account hasn't been previously set up.
From 'the authorize Windows Phone to access your account' screen, tap connect.
Enter Google ID and password
Tap Sign in.
Review the disclaimer then tap Accept.
If presented, tap connect.
Enter the email address and password into the appropriate fields then tap next or sign in (located in the lower left).
If account settings aren't auto-detected, they can be entered manually (begin with step 3).
If presented, select one of the following then tap sign in (located in the lower left):