I thought you guys might be interested in this rather challenging commission I'm working on? I'd also be very grateful for any advice or suggestions anyone might have, especially if they've tried this sort of mapping before!!
Firstly, you probably have to be around my age to remember computer games like Zork and similar, which were extremely popular in the early days of home computers/games machines. The genre is apparently now labeled as Interactive Fiction (IF) and still has a following it seems.
Basically IF games are generally text only adventure games where the player navigates using short commands at the prompt, having read the descriptions provided. Actual movement is usually via the 8 points of the compass and "up" "down", with the occasional excitement of "in" or "out" possibly!
The long and short of it is that I am attempting to create a map of one of the more recent creations in this genre which presents several challenges I found attractive.
I can only ascribe this attraction to some strange mental aberration.
A map exists in pdf format

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the challenge is to draw this with a bit more "stuff" to it yet retain the north, east, south, up, down etc nature of the beast. For this I have the "blow by blow" text of the game from start to solution with all the descriptions of the locations...

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[the room labels are just placeholders at the moment]

Issues
North is traditionally "up" on the page, which means that anything going north and "down" creates a graphical issue of how to depict downward stairs going away from the viewer, and so forth. The same applies to things like streets running east/west where the buildings south of the street will obscure the street itself.
Then there's a whole bundle of fun to be found with cellars and sewers running under other "stuff".
Finally, as a little bit of joy, one of the "tricks" of the trade is rooms where several of the exits lead back to the same room: a mechanism used to complicate the issues of mazes in the game...

I can't provide the full image since this is a commission but I thought I might share some of what I've done, or yet to do. Taking on-board a comment about Plumton, I've been doing this in GIMP using he standard single brush, which gives me rather more shades of "dull" to play with.
Overall the look is supposed to be mystery, horror, rainy, wet and creepy sorta stuff. Oh, and Dark.

It's taken me a lot longer than I imagined so far, a lot of work goes into just getting the layout not only functionally correct but also artistically "not rubbish". Bah.