Visitors appear randomly depending on how many dinosaurs you have, if you have few then there will be very few visitors. I recommend putting the buildings near where visitors abound (check your roads and where visitors are more crowded) there can be a right place, in my park, down where is the hammond creation lab in space I have 3 enclosures attached (including the hammod creation lab) and what remains is used to place a hotel, viewpoints and what remains the monorail station and clothing stores, food, security buildings, against storms, and the game room. in the middle where they give you the expedition, I fill it with buildings against storms and with some other clothes, food, etc.
In a small enclosure just above the hammond creation lab (in the narrow space) place a small cage that connects the middle area and the area below with viewpoints and towers. I fill it with about 10 Struthio, Gallimimus and Archaeornithomimus (just so that it generates more visitors to the park) one of the three enclosures below i placed a Triceratops, Torosaurus and Styracos (Chasmosaur not, they are very difficult to keep happy) right next, place a Rex modified but I did not make all, at below of paddock (the hole in end) this place is perfect for another monorail station connected with store and viewing points, and the hammond creation lab, i fill with a various herbivorous, in middle zone in the free zone, I made a small enclosure for modified Ceratosaurus and another at the bottom with paquicefalosaurus, which ended up being for Metriacathosaurus at the end. all that remains is to place buildings where they fit..... sorry for my bad english, I used google translator