HeatherMassages, not sure if you're starting out, or needing help with existing clientele. Particularly when you are starting out, you have more time than money. Giving regulars a money discount can be the difference between being able to pay a bill or not. So don't offer them financial incentives, give them bonus time, you have the time available, you don't even have to promote it as an incentive, just gift them with some extra time every so often. Don't do it EVERY time, they will come to expect it, and as you try to stop gifting it they will feel short changed. When you do do it, make sure you check in with them first that going over time is OK for them today, you think they deserve a bit extra. That way you have the flexibility not to do it if you get another client, or you can choose to do it when it suits you.
Once you become busier, you will have more money, less time, and you can reassess what you do then.