I'm not there right this minute, but it hasn't been long! My twin sons are almost 17. One got his license last summer; the other is in no hurry, and I'm not pushing him.
BE PATIENT!! Learning to drive requires a LOT of multi-tasking, and while it can be nerve-wracking for us to sit in the car while they try to figure it out, the more calm and cool you can remain, the better you'll be able to teach him. If you start to panic, have him pull over into a parking lot or the side of the road so you can cool down. Ask him if he understands why you got flustered, and if he doesn't, explain it gently.
We felt the best thing we could do for our kids was to give them every possible opportunity to drive. The more practice your DS gets with you in the front seat, the more skilled he will be when he's out on his own. If the two of you will be in the car at the same time, make him drive.
If he is just starting and has no experience at all, take him to a big, empty parking lot (we have an event center nearby that was perfect). Let him get the feel of the controls, as slowly as he wants. Let him practice staying in a straight line. Have him pull into a parking space and back out again. Give him directions for left turn, right turn, and let him get the feel of how much he needs to slow down for a turn, or how much or little he needs to turn the wheel.
With him in the driver's seat, open all the windows, get out, and walk slowly around the car to give him a feel for where the blind spots are.
At first, keep sessions short, but frequent. On the streets, start out taking quiet streets to get from here to there; gradually let him drive on busier roads during quiet times of the day, so he can get the hang of stoplights and lane changes.
If you do drive with him as a passenger, quiz him a bit. Ask him to watch for anything you are doing wrong! Have him watch traffic, and talk about rules of the road (following distance, right-of-way, how a 4-way stop works).
Make him navigate! This was the biggest thing for my kids - they've lived in the same town their whole lives, and can't find their way around at all! Make your son give you directions, and follow them - even if they are wrong - that way he has to figure out how to get back to where he belongs.
Good luck!