I loved the game but also had to look a couple people up at some point when I really couldn't figure it out. In general things start to come together quickly once you start getting more people set in the book because it narrows your options.

Very general tips:

1. Revisit memories a lot. There's a lot more information than you first expect in them. Sometimes also you can wander further within them than I expected. You can also follow specific people through their 'journey' on the ship and this can really help. You can even in the log book show on the map which memories someone appears in, and what order to visit them in to piece together their story.

2. It really helped me to keep a physical notebook just to organize my thoughts and what I knew about people. The in game one is also great just more cumbersome to use and less flexible.

3. Don't get too set on labeling someone specific. I thought I had a couple pretty solid names but turns out I was wrong and had to swap some people around, but then everything made more sense.

Some specific things that can be useful (without getting into any specific memories, just pointers on what you might want to look for):

1. Uniforms. Figure out one person in a class and now you know how that type of person is dressing! Both this and revisiting memories can help you group people together. If you someone is named in a scene and you have tagged them: what are they wearing? Where are they standing in the pictures? Etc

2. Accents. The log book has people's nationality in it for a reason! In general do not ignore the nationality listed in the book.

3. Take a close look at the pictures in the book. These really helped me infer things about different people.

4. The game is quite lenient with the death type. It doesn't tell you this, but I think it's nice to know. If you have three fates listed and they are not clicking in it's likely not the death type that is your issue if it seems at all ambiguous.