Spray Tanning is one of the most hygienic treatments that you can do, remember your client can leave their mask on right to the end and you can then just quickly spray the face, anyone who I have taught will know this routine.
Everything that the client is wearing will be able to be thrown away, sticky feet, paper pants, mask, hairnet provide a large open top bin in the room that they can just drop everything in without touching anything. I would also put all the above in baskets so that you can just pick out with a freshly gloved hand and hand to your customer. I would ask clients to bring their own face wipes so that different people are not touching the packet each time.
New gloves must be worn for each customer and a plastic pinny, we already have high standards when it comes to treatments anyway, hair tied back so you don't have to keep touching it, leave jewelry off the fingers and wrists so you can keep cleaning the area in between clients. Obviously a mask must be worn, a visor if you want to, but I would say with the spray in the air it may cover the visor. When applying barrier cream I would ask the client to apply it or use prep spray.
A clean towel at the bottom of the tent and I would use a gentle disinfectant around the front of the tent where clients tend to grab on when they are getting in and out of the tent.
Machine and Gun
Get a Dettol wipe to wipe over your gun after each client
Wipe over the handle after each client comes in and out of the spray tan room as well as all surfaces.