"Whenever you feel like it".
You have to feel like a massage and be in the mood for it. That may be once a week, once a month, or once every 3 months - no right or wrong, good or bad. It isn't like the dentist where you're meant to make another appointment before you walk out the door. Your body revitalizes and recovers from stress and fatigue when it is receptive to the benefits of a good massage. If you're feeling off-colour, a flu or just not in the mood, you may just need to be left alone and not have me moving things around.
Most of my clients come to me when they're feeling stressed and run down. We hold tension and stress in obvious spots like necks and shoulders because our bodies are very good at 'taking up the slack' but it has to stop somewhere and that's where we tend to tighten up.
So, if you have a massage and it helps, give yourself a few days to hopefully enjoy the renewed vigour into your muscles, and then you can think about another one.
The reality is that our lives are so frantic, any good work I might be able to do tends to become undone after a time and you may then feel like another massage.
It's just health and body management and looking after ourselves.
An occasional Gin & Tonic has a lot to be said for it as well.....