S.K.
K.,
I agree with you on potty training early. When they are little and agreeable is so much easier than when they are older, stubborn and set in their ways.
I used a book called "Toilet Training in Less than a Day" with all four of my kids and was very happy with the quick results. They say you can start as early as 18 months with good results. I will say you have to follow the book like a recipe to expect results - picking and choosing ideas out of the book will probably get nowhere. My first three were toilet trained just after turning two and I felt like I had missed the window of opportunity. With my fourth child, I started having her sit on the potty right after dinner while I ran the bath water when she was about 16 months old. It was a 50/50 chance she would actually pee at first, then she got the hang of it. She started going after breakfast and lunch, too, and on her own initiative. When I finally potty trained her at 23 months, it took about 2 hours and she had it down. The only reason I didn't potty train sooner was because of the cold weather. Kids need to be dressed in a way that they can get their pants on and off by themselves. I left my kids in a short t-shirt and baggy underwear for at least a week or two after training. I suppose you can just turn the heat way up, but I was too cheap to do it.
The other good preps you can do are teaching your son concepts like up and down, dirty and clean, wet and dry. Teach him to dress and undress himself - especially pulling pants up and down. Have him clean up after himself - put his own clothes in the laundry basket, his own diapers in the garbage, his own dishes in the sink, etc.
Good luck,
S.