The easiest and non-tech way to deploy your own private instance is using elest.io as detailed here.
Just login or register at elest.io and the go to https://dash.elest.io/deploy?soft=Penpot&id=121
Click on the “Create Service” button and voilá, just wait a few minutes until the instance is launched, wh en you se the status “Service is running” the instance will be completely ready.
To check your instance url click on the penpot service and in Network/CNAME you can find the URL.