Well that all depends on the person...Some people tan easier.. I have been going every other day and going in for about 9 mins in a MEGA bed. Which is the strong one..Equivalent to about 18 mins in a regular bed..
i'd start now if you want too. start low, build your minutes. depends on how fair you are, but go every other day unless you are pink or burnt. if you are wait till the pinkness goes then go again