It's no big secret that in Mario Kart, you can start each race with a turbo boost by punching the accelerator at the perfect moment before the race begins. The question is: How do you get the timing right?
The starting boost in each Kart game works a little bit differently. In Mario Kart 8, the easiest way to master the starting boost is to watch the numbers on the screen as they countdown, specifically the 2.
The key to getting the maximum boost is to hit the accelerator right as the 2 reaches the bottom of its drop:
It's tricky to get it perfect, so you'll want to practice. If you hit it too early and the 2 is still on its way down, you'll spin out:
If you hit it too late, as the 2 is already fading, you'll still get a boost, but it will be a lot shorter:
One way to help yourself get the timing right is to listen to the beeps as the numbers count off. If you hit accelerate right as the beep for the 2 sounds, you should get the maximum boost.
Watch and listen to the 2 carefully and with a little bit of practice, you'll be flying out of the gate every time, leaving your friends spinning in your wake.
Of course, that means that they will start the race with better power-ups...
Update: A reader points out that you can also time it by watching Lakitu's stoplight in the upper right, punching the accelerator immediately at his second light. It works, particularly if you follow his hand as he sets up the switch: