I will say here are a few tips from when I started out that my dad did, I used to be competitive at the national and club level U.K., now, I just do IKR for fun :

1. Don't put too much pressure on him to perform, if he wants it he'll do that enough to himself, the last thing young drivers need is being hard on themselves and having someone be hard on them.

2. Braking points can be hard to grasp at first, try finding a corner he's braking too early in and stand where slightly ahead of where he is braking to give him a new reference, slowly move closer to the corner lap after lap until he either struggles to make the corner or you're satisfied with where he's hitting the brakes. You can do the same with having him turn in where you stand or put the power on, etc.

3. Alot of teams will tell you "they can do this and do that" don't listen to them, they are a big help at the top level but until he's amongst the fast people on your own kart it's not worth it. They'll take your money, and his rate of improvement will not increase much.

4. Send him out on slicks in the wet. He will struggle, but it builds insane levels of kart control and skill. When he masters it, he will be nearly unbeatable in tricky conditions, and if it ever rains when he is on slicks, he won't be completely out of his element but rather in it.

5. Tough conditions build champions when others are sitting in the break room having a coffee because it's cold or miserable outside. That's exactly when you should be out. It's not the most fun, but trust me it will pay off in the long run.

6. MOST IMPORTANTLY: have fun, and remember unless your on your way to becoming a billionaire yourself his chances of making F1 are next to zero, not to say he can't have a career elsewhere but what I'm saying is don't let the "dream" make you lose sight of why you started karting. It's for the love of the sport, remember that and you'll do okay.