How should I go about mapping?/ Asking for general advice

[RobA]

Probably a smart idea. Though that requires fleshing out just exactly what type of land goes where a bit more. Whats beach, whats river delta(and so, where the rivers run to), amongst other things. Albiet, in some places thats obvious, knowing that the yellow represents higher elevation alot of the coast on that image just posted would likely be cliffs, for example, but not so on alot of others.
A basic outline would probably be the best precursor to figuring things like that.

And that is exactly what will dictate the coastline shapes! Without knowing if the terrain is rocky, sandy, glacial tillage, etc, the coastline is meaningless. For example, having a fjord-like coastline in a sandy area makes no sense.

-Rob A>