The first power cord that I ever made I thought made a bigger difference than an Acrotec 6 nines power cord that I thought didn't make much difference. Based on the pseudoscience (voodoo) of the time, It's braided of 18 gauge stranded wires. I don't remember how many but it was fairly thick. The entire thing was wrapped with strips of bike inner tubes to keep it tight, with the entire thing wrapped with that thick magnetic tape, the kind used in shops, and work areas to hold tools in place with heat shrink on top of that and a blue braided cover and decent plugs. All truly done with nothing special materials. The idea of the magnetic tape at the time was to scatter or lessen outside electrical interference but I guess the braiding process takes care of that and I might have reintroduced noise with the magnetic tape.
Honestly, I never paid much attention to stuff (power cords) like that at the time but years later I loaned it to a friend to get his take on them. A month later I went to pick them up and I was their a few hours listening to his system with the power cord attached to his amplifier. As I was leaving he had the standard cord reattached and was playing a live Tony Williams quintet recording I just heard and his drum kit just collapsed to the left speaker. We put the homemade cable back in and within a few minutes back to listening, the soundstage changed most notably Tony's drum kit was spread from the left speaker to the center-left of the stage. Neither of us could figure out why that would happen but it was repeatable. This was really one of the first times I noticed such a big change with cables and a power cord at that. Since that time I paid much more attention to powering my system.