I will have several school visits coming up. What type of attire is considered proper when touring a school and talking to the admission committee? Any advice?

I have an aunt/uncle who graduated from a specific Law School I'm applying for. They were very accomplished at this school and have gone on to become very successful in there career. My question is it proper for this person to right me a letter of recommendation for this school, or possibly another one? If this person is happy to help is there any part they can play in helping my admissions process?