1. Click Add new in the left panel of the main window. Choose the device type in the wizard:
2. Enter your login and password:
Sign in using application-specific passwords in case two-step verification is applied. See in detail here:
3. Once the account is successfully connected, tune Connection settings:
4. Now you can sync calendars, contacts, folders, pictures and music between Google account and your Mac.
For example, you can sync folders between your Mac and Google Drive: