I got custody of my 10 year olds daughter. How to get ready?

my friend stacy has been having a lot of problems. She has 3 kids two of them i basicly raised. I live in SC and they live 900 miles away. I moved to SC to start new. A few months ago i got a call from sky (the 10 year old) she was telling me she wanted to be with me, and that she missed me so I felt so bad i was thinking about moving back. But i cant because of my job. So i spoke with her mother and she decided to give me custody because she cant handle it. They lost their house and she is a single mother. I don't have any kids and am in a great relationship. I just want to know what i can do to make the move and transition easier on sky. What should i buy her, I am so lost. and I am leaving monday to go get her. Please help.