There is a map feature. If you keep wandering around you'll find it eventually. If you need to know though someone did a speedrun of an older version, which will direct you exactly where the map is. However, I HIGHLY recommend trying to play without looking at the walkthrough. If it proves to continues to be a problem for 10-20 minutes without finding anything new(doesn't have to be the map), then I'd watch it. You don't have to worry about accidentally missing the map, it'll be forced onto you eventually.
The video has poor FPS though, so I'd just hop through to get the gist of it if you decide to use it. 9:40 mark for when the map is obtained.