I have a 16 month old Arabian Mare, I don't have an indoor arena to work in this winter so what can I do to keep her training up? I have an outdoor arena but it's not mins and I pay to use it, but I don't have access at all to an indoor arena.. Please help... Any suggestions!

I just got a 20 year old Arabian, Pinto cross, she is a little sway backed, and hasn't been rode by a adult in 14 years, She was used for breeding. I was wondering what I needed to do to get her used to haveing me in her back, she is good with my daughter and other kids, but when I get on her she just walks really slowly in circles and trys to see what I am doing. I am afarid to hurt her. Am I doing something wrong? Should I put more padding on her back? Please help...