Watch this video from our very own JeepzillaJoe to learn about the proper way to use your machete.
As for the torquing and sliding, it sounds like you are trying to use force instead of technique to do your cutting. Your machete should be sharp (it doesn't really need to shave, but it should slice paper cleanly in my opinion) and I like to round off the grind line so that the machete can bite deeply without having that shoulder to contend with. When cutting, utilize the pinch grip that you see in the video, and leverage your body mechanics--there is really not much call for bringing the machete way over your head and taking a huge swing at something when you can drop your weight and flick your wrist instead. Most times you will also want to cut at angles, but be sure not to cut at too steep of an angle or your machete will tend to bounce or slide on the surface of what you are attempting to cut--a 45 degree angle to what you are cutting is usually safe, but by no means the only effective cutting angle.