You don't necessarily need to make your own maps or keep your own journal or notes, though it's easier if you at least note down names and subjects to talk to them about. You can also get by without using the map that comes with the game, though it makes life much easier when it comes to navigating, and it hints at useful or interesting locations you can try to reach.
However, reading the manual is a serious must. For example it tells you how to use the basics of magic in an anthropology article, and gives a lot of hints about how to interact with the environment and what tools, modern and otherwise, will be useful. It's probably possible to win without reading it, but the game will be a lot more frustrating, not to mention confusing in terms of plot, if you skip the background.
