Hi Judith! I'm actually a singer myself :D

I'd recommend advertising your teaching studio at local schools and community centers to start off. You could also see if there are any community music schools that are looking for new teachers or coaches. You could also advertise your studio on craigslist, I have a friend who's had great success with that! But to do all this you should make sure you have a website or something for potential students to check out to see your pricing options, location, and a little bit of information about you. I highly recommend Wix for creating a website, that's what I used. You can even use it for free! Check them out here: http://www.wix.com/.

Let me know if you have any questions!