Make sure you hard pack and water it so you dont get dust on your cars becasue it just makes a mess.

Spread around powder detergent on the dirt so it hold water longer. Spray paint lines on top of the jumps it helps creat better defintion and its easier to see.

water the track and and sweep it off to keep it hard back and from getting dusty. Regualr dirt can make good tracks. if done right. but can get dusty and rough fast. Clay dirt makes the best tracks.

Regualar dirt also doesnt makes good jumps becasue it is what to work with and get those sharp edges. I would recormend building jumps out of wood then coving them in dirt so you can always change them around later and they make it real easy to work with
Plus you dont have to keep stacking layer on layer of dirt.