I play guitar. There’s a thing, kinda unofficially understood, that guitarists do, called noodling. Here’s my attempt to define it when it was discussed on the Acoustic Guitar Forum:
So - in your area of art and/or craft, is there any equivalent? Tell us about it.
Kind of. I write (nearly always for children) and if I don’t know how to get to the next plot point, I have the characters talk to each other. Sometimes they tease each other. If they talk enough, sooner or later I’ll figure out how to get the necessary information out of someone’s mouth.
I occasionally make woodcut puzzles. I draw a basic plan and then go to it on the scroll saw and trim with band saw and belt sander for depth. It is all fairly free form and some finished pieces are pretty open to interpretation. But it is fun and entertaining.
I enjoy writing poems. I once wrote one just to see if I could use the word “scent” as 3 different parts of speech in the first stanza. It became a nice little thing about salmon spawning in which I likened DNA to the Gordian Knot. I would never have gotten to that without the noodling.
Similarly to Dendarii Dame, I like doing voices. Smart-ass, mostly. I strive to allow whatever is coming outa the brain through my mouth to do so without censorship. If I enjoy the character, it’s easier. I’ve gotten several ideas this way.
Doodle. In my case, it’s “doodle”. To relax, I haul out my sketchbook and start drawing semi-randomly. Sometimes something come of it; sometimes not.
The closest comparison I can make to noodling is ( I make primitive bows and arrows) my endless designs of future projects and the mathematical projections that accompany them.
As a former sport-fishing professional, when I noodle I expect several fish and at least one sore wrist. Pretty much the same as when I dapple.
Or tickle or guddle?
Another writer. My equivalent happens during my daily walk, when I work out what I’m about to write. The characters chatter to each other, difficult plot points get mulled over, neat new ideas pop into my head, and sometimes lightning strikes and I end up staring slack-jawed into the woods. With luck, I’m raring and ready to go by the time I get home and sit at the computer.
When I need to work through some ideas in Photoshop, I’ll make a desktop wallpaper. All my favourite techniques come into play in some way; isolating images, layering textures, using fonts, playing with colour combinations. It’s usually an hour or two of arseing about, and about half the time I delete it afterwards, the other half I keep it and use it on my PC desktop for a couple of weeks.
Crochet a flat circle with cotton thread… Coaster,elbow pad,make it bigger it’s a placemat…
When I’m thinking, I draw graphs to illustrate the relationships between parts of the problems. This isn’t doodling, it’s just sort of visualizing things. I actually have a visualization scheme I formalized for doing plots for novels. It would be good to computer ize, but too lazy.
I need something like this, I get so far into a concept and the relationships between things start becomming obscure and confusing. brings me to a hault everytime.
I own* drums. I do long, tedious solos. Even the dogs lose interest. “Droodling”.
*Notice I didn’t say “play”
Every grocery list has scraps of dialogue. Every list of things to do has possible character names in the margin. I “see” memories in page form with paragraphs and scene breaks. I forget and let the bread burn while I jot down the word I’ve been looking for. While riding past evening lit houses I wonder what’s going on inside.
Theatre games, often employed at the beginnings of rehearsals, are designed to activate the imagination and loosen the inhibitions / reserve we carry with us day-to-day, so we can be present and open and genuinely respond to what’s happening in front of us.
We also often try several variations on the same line, experimenting with what emotion and how much feels genuine. Actors generally call it “play.”
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Stream of consciousness writing is noodling in word form. But don’t tell that to James Joyce. 
I play guitar unplugged while watching TV. Most of the time I’ll just be playing simple chord progressions, or a song I know by heart. Any time there’s a song or commercial jingle on, I’ll either try and figure out the chords, or improvise some countermelody or harmony to the melody.
I just realized I have been noodling all along and not realized it. I pick up small sticks, chopsticks, plastic, metal whatever I can find and fashion into bow designs I might like to try.
And a lot of my sketches are the same thing as another one. Some of them I kept doing and doing until that one time I finally got it right(ish); others are just a theme I happen to like.
When I’m solving problems, specially data-related ones, I think in pictures. Ever tried to explain to someone that the light blue rectangle thing that’s got like 6 dimensions isn’t quite hooking up to the deep red rhomboid? I was so happy that time there was another person in my team who did the same, we pictured different figures mentally but could “talk” in doodles quite well.