Registrar and celebrant at the wedding

Hello!


I’m getting married in October and we wanted to do a handfasting and unity candle for our ceremony, I’ve ready that registrars can’t perform these as the legal and belief aspects needs to be kept separate.
I will message the district we are getting married in but I was wondering if anyone has experience with having both a celebrant and registrar at their wedding? How did people make it work, did you have the celebrant lead first and then go off to sign a marriage certificate with a couple of witnesses? Or both at the same time? I’m just very confused and any experience or help would be amazing 😄