Filthgrinder: So, you have to stick to one "known" area at all times?
Kinda ruins the exploration part. They should rename the game to "Let's map an Island"
Well, thanks for the explanation.
jefequeso: Oh, one other thing... when you triangulate your position, I believe nearby landmarks become known. So that makes things easier as well. And I'm now at a point in the game where there's no clear path to travel on, and I do kinda need to start exploring on my own. So I was incorrect. It's not all supposed to progress on a set path.
It might be better described as a series of short linear paths with a bunch of nonlinear exploration inbetween, i.e. you'll explore until you find a lead on where the next part of the cure is, head there, do that, then continue exploring.
Also, keep in mind that you don't need to (and can't, as far I'm aware) map the entire island. You should be able to find your way through forests and stuff with your compass as long as you pay attention.