The fastest way to find a lost tool is to buy a replacement.
I have not got to the aeroplane construction bit yet but have built a lot of experimental machines,usually agricultural, and there is one thing I stand by,if you are having a problem with something then just walk away. For ten minutes or an hour or even over night,the ideas come easily with fresh eyes. Cheers
Repurposed tool: I use a crochet needle to determine, from one side, the optimum fastener grip through laminates / cores. I insert it, hook the opposite face, mark the front face with my thumb or a marker pen, withdraw it and either measure it or compare it to the grip of the fastener that I think is optimum. A bent piece of heavy safety wire works too, but the handle of the crochet hook is easier to handle.
When I was operating a stamping press for a summer job (a friend of my father's was the manager, and only year 'round, full-time employee), the boss told me to walk away for a couple of minutes when was getting tired. Blood is corrosive and hard to get off the machines
Less flippantly, fatigue causes people to be much more error prone, and, in the battle of fingers vs stamping press, the fingers lose. No sane manager wants employees maimed, and will make serious efforts to prevent it.
Another thing is to make sure everything is light enough to move with available equipment, and to make sure that any lifting is done with attention to one's back.
(as a rather gruesome aside, I once worked with somebody in the aero industry who had the same two fingers cut off and reattached twice after accidents with power tools. He said he surgeon was not happy with him)
I write lists on walls. Things to do, things to buy. When I leave the room, I take a pic of the supplies list either because I'm going for supplies, or I might. When I run out of wall, bits of paper or card go up. Occasionally, I get really organised and hang a large pad of paper up. I always shop from my phone though, I usually have it with me. Bits of paper escape from pockets. I have a particularly hard time losing a wall.
Quick tip how to make note pads. Recycle office paper,make a stack and screw two strips of ply across the middle and cut across with radial arm and end up with two pads.
If you think searching your workspace for a tool that is in your hand is bad, let me tell you about my mother in law.
She has, on numerous occasions, asked if someone had seen her glasses. She now recognises a resultant eye roll as meaning 'right in front of your eyes'.