If you are planning for a traditional event, then that's it. Just send the PPen file, map file, and risk assessment to the organiser.
If, however, you are doing a virtual event (as all JOGs are during COVID-19 restrictions) there is a bit more. You will need to create the kmz and kml files and send them to the MapRun administrator. Either the Planner or the Controller then needs to check that the GPS works at each control.
Please see these guides for how to do this...
NB: Several people have commented that they made the mistake of not watching the videos on the first link through in order the first time they tried doing it.
It is still very helpful for the control sites to be marked, especially to reassure younger participants. Mini control kites can be borrowed if the area is suitable for them. Tape can also be used, but be careful as it can look untidy and lead to people thinking it is litter. Coloured clothes pegs with the control number written on have proven successful on some courses as something that is unobtrusive but easy to spot if you are looking for them.