I am a firm believer that the earlier you do it the less tug of war there is, all of mine are day trained just after 2, nights take a little longer. Here is how I do it.
1. About a month before you start training, get a little potty, and practice on it, keep it in the living room, kitchen wherever, the put it in the bathroom for a brief period of time, take him in the bathroom with you ask him if he wants to sit, don't force just ask, it can be with or without the diaper.
2. A week before the big day, start talking about it. Tell him how exciting it will be, how know he is going to use the potty like mommy and daddy, you get the idea.
3. Plan 2-5 days where you are going to be at home and only at home, and occasional trip is ok, but the bulk of time at home.
4. The big day, remove the diaper and don't go back (except at night), here is tha part that parents cringe, let him go naked from the waist down, yes you will have accidents but it is how they learn to understand the feeling and then what happens, then place the potty in whatever room he is in, it's easier for them to get to, accidents are no big deal, just say "Uh-oh help mommy clean it up, next time lets make it to the potty". Make sure to sit him down every 30 minutes and try to have him sit for at least 5-10 minutes, play games watch t.v anything, once he pee's do the potty dance and make a fool of yourself, they love it.
5. Once you have had 2 days with minimal accidents put underware on, make this a big deal, he will have an accident or two cause the underware are like a diaper trigger, and they tend to have them.
6. Have patience, it doesn't happen over night but I have done it with my last three, and had it done in a week at the most.
I did more traditional with the older ones, and it took a little longer, and was a heck of a lot harder. Good Luck!