This is essentially the over-under method. The idea is that you do a twist in one direction as you make your first loop, then a counter-twist in the other direction, which causes the second loop to sit “under” itself. So your coils follow a pattern of one regular “over” twist, then a reversed “under” twist. So the net result when you uncoil the cable is zero twists, (or at most one twist in the entire length of the cable, if you started and ended the coil with an over twist.)

Professionals use this for coiling, because it helps with cable longevity and running. Your cables never develop the dreaded twists in the first place, because you’ve never introduced more than one twist into them. And in a 50’ run, one twist is negligible and will work itself out as you coil the cable again at the end of the night.

And a figure-8 coil is basically the same thing as over-under, but laid out flat. This is handy for thicker cables that you coil in place. Hubbell Cam feeder cables, for instance. Each cable is as thick as a quarter, and there are up to five of them in a bundle. So it’s incredibly heavy and hard to work with. Instead of dragging the cable to you, you usually have a crew coil it directly onto a cart or into a case. So you’re wheeling the coil around, following the path of the cables, rather than trying to drag the cables to you. But this means you need a way to coil it flat, and a figure-8 solves this. It achieves the same twist-counter twist pattern in a much flatter (but wider) footprint.

The downside to the over-under method is that if one end of the cable gets pulled through the loop, you end up with a series of overhand knots in your cable, spaced evenly across the entire run. That’s why professionals will use velcro cable ties on all of their cables, to ensure the cable ends stay on the correct side of the coil and don’t get pulled through.

Source: I’m an audio technician. In a single shift, I’ll coil anywhere from 500’ to 2500’ of audio cable. Every mic you see on stage probably has either a 25’ or 50’ cable on it, and all of those need to be packed up at the end of the show. On a big gig, I can easily coil half a mile of cable throughout the day. I always joke that the actual show is only 10% of the job. The other 90% is cable management.