The board revolves around its longitudinal axis, like an aileron roll. To understand this motion and the direction of rotation, imagine stepping backwards off a skateboard, leaving it in front of you, then rolling it over on the ground toward you; during the kickflip, the board spins similarly, but in mid-air beneath the rider. During a heelflip, a similar trick, the rider slides their front heel toward the opposite side that they would with a kick flip, resulting in a rotation of the board opposite to the kick flip.
The board revolves around its longitudinal axis, like an aileron roll. To understand this motion and the direction of rotation, imagine stepping backwards off a skateboard, leaving it in front of you, then rolling it over on the ground toward you; during the kickflip, the board spins similarly, but in mid-air beneath the rider. During a heelflip, a similar trick, the rider slides their front heel toward the opposite side that they would with a kick flip, resulting in a rotation of the board opposite to the kick flip.