In all my many years of assembling small hardware, with my fat fingers and lousy eyes, it took until today to devise a neat trick.
m3 hardware in confined spaces, getting washers and nuts on a screw can be interesting at best, maddening at worst.
Enter the ball driver. Choose the proper size ball driver as if the hardware is Allen head, whether it is or not. Slip a nut, then a washer onto the end of the ball driver, slide them up out of the way, and hold them with a finger. Touch the ball end of the ball driver to the little dimple on the end of the screw, and let go of the washer and nut. The washer and nut will drop into place. Continue holding the ball driver against the end of the screw while you start the nut onto the threads with your free hand or by flicking the flats of the nut with any other tool handy. I used a small Allen wrench.
Putting a washer and nut on the end of a screw inside a pocket the size of a postage stamp took literally three seconds. Then I simply snugged it with a wrench.
I’ve fought with this kind of stuff, M2 or 3 or smaller for years. Tonight, five bolts in about two minutes with zero issues.