A crucial piece to enjoy AeroGauge is the fact that trying to pick it up and playing without knowing NOTHING about it will likely result in a particular way: The AI will always start faster than you and somehow stay faster than you without ways to catch up if you do mistakes...or even at all.
This is because, like I mentioned at the start, there's a drift boost mechanic that's essential if you want to see any good results in this game.
While I was thinking how would I explain the few key mechanics the game has, there's actually a place where most of those are explained and with video reference on top of that: This Speedrun.com page for the game. Big shoutouts to the guide author [ciwb / JM], who also happens to be the only person who had ever put this much effort into speedrunning the entire game and documenting all the strats [including a few bugs used].
But for a quick reference step-by-step here, the rocket start is done by holding A and B before the race starts and letting go of B when it says GO. The machine will tilt downwards if you are holding the buttons properly, and kick off with orange flames like the rest if the rocket start was done right.
Then there's the way you do boosts: You drift with the Z button, which kind of makes your machine slide to the left or right as you hold it while steering at a direction. If you do that, let go of both Z [Drift] and A [Accel] then tap A again, you'll get the boost. Although getting a good feel on how much the machine has to slide before the drift boost works can take practice.