Every business situation is unique, so it might help to have a little more background about your business. However, there are a few general suggestions that might help.
Being a web-guy myself, most of my suggestions would be internet-based, but you should only consider them as part of a larger marketing strategy for your busines. First off, a clean, friendly, and easy to use web-site can help a lot. If you're getting started you probably don't have a lot of money to spend on a fancy site, but even if it's just one simple page with your location and contact info it can help you get new clients by getting your business to show up in searches through Google or Yahoo. Additionally, most metropolitan areas have some sort of internet-based local business listing, and with a little networking with them you could probably get your studio listed. Services like that can either be free or have a small fee.
Also, having a website can allow you to start a small email marketing campaign. I don't have enough room to go into a lot of specific detail (email marketing alone is a big enough subject to fill volumes). However, you could use your site to collect email addresses (make sure you get their permission to email them - don't be a spammer) and inform your customers of upcoming promotions, events, etc. You could also have a guest book at the front desk of your studio where you can collect emails and visitors can sign up to get your newsletter.
Just keep in mind that those aren't guarantees for success, but they can be a valuable tool. And almost above all, don't forget your customer service. One of your best marketing assets will be happy, satisfied customers 
.