If you’re looking lost (like on a phone), kids or profs will stop to help. Sometimes 10 or 20 mins later you realize I just learned a lot. We had great chats at W&L and Emory this way. We really were lost. And they help the tourists 
Eat in the dining hall. Talk to the kids staffing the info desk. At ERAU when we asked where on campus to eat, they asked - do you have a car ? Enough said.
Any groups or clubs or faculty u want to meet ? Request in advance but you can also pop in to an office. My daughter got lucky with a hello to the Honors College Dean. And then money started flowing although I can’t say that’s why.
Mainly be thorough, inquisitive. Maybe walk from a popular freshman dorm to the library at night. Feel safe ? Walk a likely class route. How long ? If it’s a large school with a bus route, hop on if you can and experience it.
Lots of great things you can do. Some know right away - is it right or not. Others don’t. And optimize your time with various activities if you need that time.
Have a great trip(s).