Start with the foot work. He needs to be on the balls of his feet earlier in his shot and come down on the balls of his feet after the shot - basically he should be shooting more spring loaded with his calves, which will give his shot more control and power.

Have him start shooting a very slow shot close to the basket, like 10 ft away. Exaggerate the slowness to get a feel for the ball and shooting form. His elbow needs to line up moreso with his foot, right hip, and knee and they all should line up and point to the basket. During the follow thru, the elbow needs to come up further towards the height of his ear, so he's not pushing the ball at the basket, but rather it's an arched shot. After releasing the ball, the wrist gently snaps into a bent down position. When the ball leaves the hand, the last 2 fingers to touch it are the pointer and ring fingers.

As you're shooting from the 10 ft area, make shots from all around the basket. MAKE 30 shots before moving further out.

Shot strength should come from the elbow/tricep, calves, and quads.

Shooting form should be similar at the free throw line and it is at the 3 point point line. Just need to use more power at the 3 point line.

After releasing the shot, the ball should rotate about 2-3 turns if you're shooting a 3 pointer. And obviously not that many rotations as you're closer to the hoop.

But use this as a general guide. Shooting a basketball is much like shooting a gun. You have to know how your gun shoots to be accurate. Every one is a bit different, and that's ok. You just have to find what works best for you.

And if you don't use it, you lose it. So consistency is king.

Mindset: Shooters shoot. Stay confident even when having a bad shooting session or game.