You can do this solo with one controller in an exhibition match with no bots, simply once the match look for the little boost pads around the arena, especially the larger ones with the globe on top like the one below
These larger pads are usually located on each corner of the arena and at the sides of the half way line, simply drive through them to fill your boost gauge on the right of your screen so it shows 100 (The large ones fill instantly) then press and hold
to use your boost bar, now in this solo match you can easily drive around the outside of the arean on the walls and drop down once the boost is used up to pick up another large pad.
Here's a video
Will count for