While Jobs will usually be set to run on a recurring schedule, it might sometimes be necessary to run a Project backup manually.
To initiate an on-demand backup, navigate to the Projects tab and find the Project you wish to backup manually. Click the Backup Now button to start the backup. You will find this same button on the Job and Device cards that are linked to your Project, so you can also start a Project backup from those Site assets as well.
Your manual backup will initiate and you should be redirected to the Job History tab to see the progress of your backup.