$10 a hr sounds like a good deal. I would also have treats for her (i.e. chocolates, flavoured milk) and let her know she can bring DVDs etc that she wants to watch.

When I babysat, I found that the more welcome I was made to feel, the more comfortable I was with the kids and I felt more capable as the parents trusted me. Also helped when I accidently broke a plate and owned up when they got home. I would have found it harder to own up to a mistake if I wasn't comfortable. Luckily, they were understanding and refused to keep my 'wages' for the night as payment for the plate. Later the wife told me that she hated the plate and had been trying to 'accidently' break it for years. Apparently it was a wedding present from an aunt of her DH's that she loathed.

I agree that you start with short visits and go from there.

Have fun on your night out!