Without watching you I can not tell you what's going wrong but here are a few things you may want to consider.
1. Turning your gun down. Is too much solution coming out, wasting it?
2. Speed your hand movement up slightly. Is your hand movement is too slow, so you are over spraying each client with too much solution?
3. What size are your clients? I mean this in the nicest possible way, be we are all different sizes. A client who is a size 20 will use more solution that a client who is a size 6. Are you doing larger clients?
My advise would be to turn your gun down a little bit and slightly speed up your hand movement. Not too much, we still want to get tan on them.
Maybe practise on a close friend you new 'less spray' technique and see how they turn out. That way of it is not enough spray, your friend wouldn't mind.
Zoe x