As a wee lad I liked to stick my arm out the window of the car and, by changing the angle of my hand, cause it to go up or down or even swing back when cupped like a 'chute. Ha Ha, never belted in back in the day.
By '83 I was deep into thinking about and sketching aero cars and motorcycles. I finally brought my work into the 3-D realm then:
I guess the first "real" aero work was a college research project/paper where I built and coast-down tested aero add-ons like skirts, air dams, grille blocks, and such. The results were inconclusive.
Concurrent with that, I got my Pilot's License and that has more than a little aero training.
Later on I researched, tested, and designed bodywork for off-road vehicles. There, aero wasn't so much about lift or drag as it was about operator comfort, cooling, and other concerns.