After you create the project, you can create a service account in that project. A service account is an account that uses the credentials of another Google user to retrieve data when required. Use a service account which is used solely to retrieve and create meetings on behalf of users and the main application.

Perform the following steps to create Service Account

1. Go to the Navigation Menu on the Google Cloud Platform.
2. Click IAM &Admin and select Service Accounts.
   
   
   A new page appears.
3.   Select the project you created previously. In this case, select "aviso- gmail-activity."
   
   A new Service Accounts page appears.
4. Click +CREATESERVICEACCOUNT.
   
5. In the Service Account Details, enter the following fields.
   •  Service account name
     For example, you may enter aviso-email-activity-service.
   • Service account ID
   • Service account description
6. Click Create and Continue.
7. After creating a service account, select Viewer role from Grant this service account access to project.
   
8.  Click Continue.
9.  After granting access to the service account, click DONE.
   Your browser will redirect you to the page that lists all the service accounts.