What is a good way to market yourself as a sitter?

Hi Mallorie: I advertise on my local buy/sell/trade pages on Facebook using my link and promo code on my dashboard. The page wants a price, and since my walking and drop in prices are the same, I enter it in there with the title Pet Sitting Services. Then I put a small paragraph that goes something like: Do you need someone to walk your dog? Or how about stopping in while your gone to let your dog out for a much needed potty break? As a Rover sitter, I can do both....... Then I say just follow the link below....etc etc. I always include the $20 off your first stay and promo code. I bump the ads once a week, and check to see if they're any responses daily. I've gotten some clients from my Facebook ads. I also do the same thing on Google+.