Full Interrogation
Interrogation is a valuable skill to any sleuth. While exploring the park, ask every possible question of every possible subject in order to learn all the information you can. If you get stuck in the game, go back and talk to every person again in case one of them has new information.
Examine Everything
In every room or area, try every movement and examine every object you can. Many objects might not seem useful at first, so examine each thoroughly. You're likely to find a use for them later.
Consult Nancy's Laptop Often
With each return to the hotel, Nancy takes notes on her laptop. If you get stuck, review these notes to see if Nancy has drawn any new conclusions that you might have missed.
Take Notes Yourself
A good detective takes plenty of notes. Keep a notebook handy as you play to jot down interesting areas and situations, images and signs, and anything else that might strike you as useful.