I create a "target" in /etc/systemd/system that is very simple
[Unit] Description=SP Example Target [Install] WantedBy=multi-user.target
I then create a directory called /etc/systemd/system/sp-example.target.wants. In this directory, I put a link to my service and restart the system. It doesn't start the service, but it does start the target. I move the link from this sp-example.target.wants directory into multi-user.target.wants and reboot and the service starts.