Recruit Day Tips Needed

My class of '24 son was invited to a Recruit Day and has been in communication via email with coaches, he's very excited as this is the first time coaches have contacted him directly and there's no "camp fee." We are new to all of this and we have RSVP'd, have the itinerary etc. What do we need to know? What to wear (me included lol)? What questions should we ask? I guess why tips or do's and dont's would be appreciated! ⚾