this is something that i had to solve recently and if you want it insanely slidey, the best thing to do is go to the dollar store or any store and buy the cheapest candles that you can.
Cook the candles with vegetable oil and then let it solidify, either using the fridge or just let it sit on the counter.
This made the wax insanely slippery for my pvc pipe rail i just built along with my steel rail.
thats where I got it from. it works amazing, definitely try it.
i would recommend using some kind of a pie silver cooking pan or whatever something bigger then a red bull can so that your wax stick isn't so small though.
Other then that definitely give this a go it works amazing!
O and I just granola oil or something instead of vegetable oil, I'm sure its all the same. still worked amazing.