Step 1: Signup for Wasabi account in https://console.wasabisys.com/
Step 2: Get the wasabi Access key and Secret key : go to https://console.wasabisys.com/#/profile -> API ACCESS -> Create new Access key as shown in the images below


Step 3: Select Wasabi as the Backup method in the WPTC plugin fresh install page and enter the keys created above.
From now on, your backups will be stored in Wasabi by WPTC.