When pulling fairly long runs of cable, a reel support is a really useful to to have. The first time I really needed one, when pulling eight or nine runs of cable from the attic to the basement, I was fortunate to be able to place a broom handle on some nails and position it directly above the opening I was pulling down.
In Alexanders closet I have to drop two runs of 14/2 two wire, and one of 12/3 three wire, so I built this simple reel holder. There are two matching bases built out of 2x4, 15" for the riser, 12" for the edge foor, and about 8" for the flat foot, glued and screwed together. A hole is drilled in each riser about the same diamter as the bar, which can be of any length to accommodate one, two or even more rolls of cable. In this case, the bar is a cutoff section of the century old heating water supply pipe I removed from the floor in the last post.