- Checking out the supplementary diary that comes with the game is a good idea. It's not necessary to read the entire thing but it helps setting the mood, and it does include a couple of codes and passwords in it.
- The vast majority of random stuff you can pick up isn't needed for gameplay progress. Consider what might be of legitimate practical use and pay attention to the game's descriptions of things when you try to "Use" them and you should largely be fine, the game doesn't veer especially far into bizarre adventure game logic.
- Avoid dropping anything that seems remotely important in places that seem like you might not be able to access later, primarily meaning the locations where your targets are. Save regularly in different slots to avoid having to go too far back if you do softlock yourself.
- Make use of the small zoom-in view and look carefully through busier parts of the screen because some necessary objects can be very hard to spot and mixed up with other things. Notably one section requires distinguishing between a "Rail" and a specific section of it labeled "Railing".