Step 1: Goto the developer section of the Google i.e.
Step 2: Create a new project by providing the project name followed by Create button (it takes some time so wait)
Step 3: Now select your project.
Step 4: Select "APIs & auth" followed by the credentials.
Step 5: Create a "New Client ID" in the consent screen provide your product name and email.
Step 7: In the "AUTHORIZED REDIRECT URIS" Provide "http://community.askgargi.com/" (dont forget /)
Step 8: Press Create Client ID
Step 9: Create an API key. Select "Server Key" and provide IP address (as shared with you)
Step 10: You are done.
Step 11: Now share the CLIENT ID, CLIENT SECRET and API KEY on the control panel (admin->control panel)