My son was "lazy" when he had a diaper or training pants on. So what I did was have him run around nude and sent him to the bathroom every 15 minutes to start. Then I'd increase the time in 5 minute increments. I did this when he was 3, but then that was when he was ready to do it.
I agree with jbalch! I saw your in the 1-2 age range,, for me that was too early with a boy, he was frustrated and so was I, if you wait closer to 3 you will probably have an easier time of it,, we did it in a weekend at 1 month shy of 3!