Spin Dash Achievement
Did a Boost-Start in each vehicle mode
To get the best possible boost you must hit the just before he says the number. To help you time hitting the screen will fade then he will say three. Do this 3 times and you will go from red boost to purple to blue. Try to get a feel for the rhythm and you'll have it in about 5-10 restarts. Be sure to choose these via single race. The stages you will want to do this on are:
Car: any stage
Boat: Cup 4 Stage 2: Adder's Lair
Plane: Cup 3 Stage 1: Dream Valley.