Create a User based service file:
cd ~/.config/systemd/user podman generate systemd CONTAINER-NAME > container-CONTAINER-NAME.service
Edit the service file and comment out the PID= section. The allows you to not have to create a new service file each time you re-create the container.
Reload the systemctl dameon as root:
Enable/start the service up. Do this as the user it will run as:
systemctl --user enable container-CONTAINER-NAME systemctl --user start containre-CONTAINER-NAME