I have done a lot of cat and dog rescuing/fostering. It is so incredibly rewarding to know you are saving a life. It's important to be patient and realize the dog will likely be nervous/scared at first... esp. a pit mix if it's been in a bad situation. When I first started doing it, I found communication with the organization leaders and watching a lot of The Dog Whisperer helped me a ton. There is so much support out there for you to learn how to do it effectively.

The thing that got me through the harder times with dogs and cats that needed more help with training and stuff was to remember they just need guidance and WILL learn-- sometimes it takes a little time, but they always do. Same with medical stuff. I experienced animals that sometimes needed a few vet visits to deal with issues that came up when they weren't being taken care of. I just kept reminding myself it wasn't worth getting frustrated with them because it wasn't their fault.

If you have any specific questions, feel free to ask.