1. Go to the Google API Console at https://console.developers.google.com.

    If you haven't created a Google account, you can do so now.

  2. In the Projects list, select a project or create a new one.
  3. On the left, click Credentials.
  4. Click Create credentials, then select OAuth client ID.

    If you are prompted to configure an OAuth consent screen with information about your application, you can do that now.

  5. Select the appropriate application type for your project and enter the following information:
    • Name: The name of the OAuth client ID, not the display name of the application.
    • Authorized JavaScript origins: The origin URI of the client application, for use with requests from a browser.
    • Authorized redirect URIs: (Leave this value blank for now.) The path in your application that users are redirected to after they have authenticated with Google.
  6. Click Create.
  7. In the OAuth client window, copy the client ID and client secret to a secure location.

    You can always access the client ID and client secret from the Credentials page in the API Console.

For more information, see https://support.google.com/googleapi/answer/6158849.