How can I build my aesthetics business?

I am new to the salon and spa business. I am an esthetician and do facials, waxing, makeup and more. I have been at this spa since January and am hoping for examples of ways to get new people in to see me. I have tried certain promotions such as "first time client take 15% off" I always follow up with postcards saying thanks for coming in, next time bring this card and recieve 15% off. I know that this business takes time and word of mouth I just don't know how to reach out to people who I haven't seen before. Any thoughts or ideas would be helpful.