There are two ways to look at these. There is pricing for your services before you do a treatment and there is the end of the year "what return did I get for my investment of time and money"
If you keep your labour costs to between 33/30/25% of your turnover you're doing ok. That means that for every £1 you pay out in labour you need to make £3.
I work on £1 for labour, £1 for the salon, £1 for the client treatment as a rough rule of thumb. I then finesse my overheads to try and get the salon costs and client treatment costs down to 25% each (retailing products helps!) that gives me my profit !