I started at the front desk letting know what I'd like to do. It took a bit but they got me to the right person. Once you are there, there is usually some documentation you'll have to sign to ensure you follow whatever the hospital's rules are and if they allow it. After that keep in contact with your POC and hope they can grant you a visit in costume. it's touch and go depending on the number of kids and condition, but they'll usually work with you and schedule a time.