This might be a little complex but what I do is:

1. Work out what it costs me to run the salon every week.

2. Work out how many bookable hours I have a week, and then take 66% of that number (even the best stylists will only average 66% every day)

3. Divide the figure of #1 by how many hours in #2

4. Add to this product cost for the service and then add another 60% as my profit before taxes.

SO if it costs me $3000 and I work 81 hours ( thats 27 by 3 stylist) it costs me $38 an hour to open the doors, add the profit means I must make $61 an hour. If a haircut takes 15 minutes I must charge $16 a cut ( we work on a tiered price list so $16 would be the lowest and it would increase from there). If I need a colour price it would be 15min to apply, 5 minutes to rinse so thats 20min total thats $20 plus colour cost of $8 so the price of my colour would be $28.

Hope you can understand this and it helps.