I bought a set of small LED lights from Amazon, the tiny kind on clear-coated copper wire. They come in a small round container rolled around a large toilet paper roll, which holds the transformer and cord. I took them out of the box once or twice, looked at them, and then set them in one of the geological epochs on my desk. Come Halloween, I rescued them and went downstairs with some vague thought about wrapping them around the stair spindles, whereupon somebody was quite dismissive, until thoughts of a season which shall not be named until after Thanksgiving occurred. Then somebody took over, unrolled the lights and headed up to the top of the stair with the end of the string of lights. Now the only outlet anywhere along the main stairway is at the bottom, so I didn’t think starting at the top with the other end of the lights was really a great idea.
After a rather overlong discussion of what might work, and we started wrapping the spindles (from the bottom) which ended up with us re-wrapping the wire on an actual toilet paper roll to facilitate passing it through the spindles. After a few spindles were wrapped, it became obvious that there was more spindles than wire to wrap them in, and the process was reversed and a weaving process was started that brought the lights up and down the stair way about four times. A couple of rubber bands have been added to provide stability to the end-points (the spindles are smooth symmetrically turned wood, fatter in the middle than the ends).
I added a timer to the transformer for the coming months of darkness.