I find myself with a darkroom which shares space with other objects (LP collection, computer table. It is used as film manipulation for now, do not use it that much, navigating is a bit tricky, no muscle memory yet!
Any tips?
I think it would be best for me to define an L-shape corner, and make provisions for easy reach to a minimal light needed to navigate back to main room light switch.
Put your film, opener, reels, and tank inside a large printing tray or oversize baking pan. Then you don't need much muscle memory, and a dropped item can't go far.
For "minimal light," Harbor Freight periodically gives away free pocket flashes. I get several years of service (with occasional battery replacement, of course) out of one.
I wear a small red LED light on a neck lanyard when I'm in the darkroom - minimal light is always at my fingertips. It may or may not be safe for photo paper, I've never checked, but I don't use it when paper's out (and it's obviously not film-safe!). It's fine for navigating and poking around in very dark corners.
You can also buy luminescent tape. It gets energized by ambient white light and then has a long-lasting soft glow. You could put a few pieces in strategic locations as guides. I placed a small piece of it on the light switch, facing upwards away from where film and paper.
You could count steps between each area where you need to work. Keep everything as organized as possible. For example, I have 8 drawers in my enlarger table that contain things I might possibly need in the dark, and each drawer holds the same items that it has for 40 years. I can put my hands on anything I need in complete darkness. Don't worry, you will get very good at moving around in the dark after awhile.
If you are expecting to work in a space while in the dark, then it pays to think about layout and the specific designs of the furnishings in the space.
Have a record collection in the same area? - Get them into a splash resistant cabinet that has no sharp edges, and minimize what you can stub your toe on.
Look around the space and consider anything that looks uncomfortable to run part of yourself into if you go fumbling after something you drop in the dark. - Doesn't really matter if the uncomfortable aspect is how much it is going to hurt if you bash your head into it while thinking you're still another foot from it, or the pain to your wallet if you break it.
Taking the time to think "what are the biggest ways I could screw up in here" is the first step to removing issues.
The less 'stuff' you have at hand, the less stuff there is for dust to collect on, and the less stuff you have to root through to get the thing you need: Figure out what you need for your current ongoing projects, and get as much of anything else out of the directly accessible space.
I agree on good work trays (already implemented), streamlining the space with a thought on safety, a big item (underway), and helpers like a handy lanyard back-up light (got one!).
And the pull at the bottom of the chain is a really good place for a strip of that glow-in-the-dark tape. As long as it's not directly over your film changing surface or trays, it won't fog, but it'll sure make it easier to find the chain in the dark.
Keep a small torch handy in your pocket (or mobile phone etc) so you can have light when you need it.
Put your work area within easy reach of your light switch.
Make sure there are no trip hazards between your light switch and your work area.
Paint a blob of fluorescent paint on the light switch.
Put your film, opener, reels, and tank inside a large printing tray or oversize baking pan. Then you don't need much muscle memory, and a dropped item can't go far.
Keep a small torch handy in your pocket (or mobile phone etc) so you can have light when you need it.
Put your work area within easy reach of your light switch.
Make sure there are no trip hazards between your light switch and your work area.
Paint a blob of fluorescent paint on the light switch.
I replaced the ordinary trim plate on the light switch with a "guarded" plate. You can't accidentally turn on the light, but its easily used with a little thought. I found such a plate at my local Lowe's big box store.
Small strips of self-adhesive fluorescent tape (or even glow-in-the-dark star stickers; I like those best) work fine and won't fog film if they are positioned well away from the work area. I place them on timer switches, light switches, dangerous cabinet corners, etc.