For the dog sitting, you could make up a flyer and take it to local vet offices. I do a lot of pet sitting but only from word of mouth (I really don't want to advertise) but the people I started out pet sitting for were from the vet office I worked for and then the local humane society that I'm involved in. Now they all recommend me to other people. I would just make up a flyer of what you can offer (staying at their house, dog staying at your house, or just coming over a few times a day, etc.) and put them up at vet offices. When I worked at a vet we always had clients calling asking if our employees did pet sitting or if we recommended anyone, so that's why I say that.