Your abilities are some of the most essential things you will need to go fast in this game. You have three abilities that help you the most: your powerslide (which helps your turns more), your tilt (used to take really tight corners in conjunction with the powerslide), and your boost (pretty self-explanatory). One of the first things I started doing was using short bursts of speed with the boost, thinking each small burst gave you more speed that holding it, but that is not the case. Your boost is meant to be held, so hold it! The only time you would really want to use short bursts would be if you wanted to save some for a long straightaway but also wanted to use some small amounts before. And as for your powerslide and tilt, first comes the powerslide, and then you want to use tilts in case just the powerslide wouldn't be enough for the turn (there are a couple of cases of that in the run). Hold powerslide and then use tilts during the powerslide. And that's how you use your abilities well!