P.H.
I expect you'll get a lot of advice on this because there's really no right or wrong way to potty train. In most cases it will be dictated by your child's personality and readiness as well as your ability to "handle" the process.
I have twins who are now 11 yrs old, so this was a while ago for us. My daughter was more than ready and given her independant nature, it came very easy for us. My son, however couldn't be encouraged to do anything - he was happy to stand there and be her cheerleader! He potty trained very differently.
We opted to use a flip up potty seat that attaches to the toilet. My parenting philosophy was not to start something that had to be undone later. So, we opted to go right for the toilet, and skip the potty chair as it would be just another transition to work through. I also didn't have time with two running around to maintain a potty chair. With boys, you have two main options - standing or sitting. My husband and I decided sitting was for toilets and standing was for a urinal. Since we don't have a urinal in the house, we taught our son to sit first.
We helped him be ready by first monitoring his beverages. I gave him so much water in the morning, he HAD to go sometime within an hour of breakfast. So we started to add the routine of sitting on the potty for 5 minutes (using an egg timer) after eating breakfast and before getting dressed. If within 5 minutes he didn't do something, we'd play again for 15 minutes, and go back on the potty for 5 minutes. Once the routine was established, the whole process seemed to flow better.
He actually picked up #2 quicker than #1. We didn't use pullups either - too much like a diaper. Straight for underpants that he had picked out at the store himself and was excited about.
Our main issue with him was the nighttime training. He was a deep sleeper and afraid of the dark so getting him to get out of bed in the night was a challenge. We put nightlights in his room, in the hallway and in the bathroom so there was a lit path. He didn't get it about 4 days so we opted to stop the night time training and concentrate more on the daytime. He wore a diaper to bed, and pants in the day. (Going from two kids in diapers to one diaper a night was heaven!!) When night time training, I'd also layer the bed with bedding to make night time accidents easier to manage - first, a waterproof mattress pad, then a sheet, then a second waterproof pad almost the size of the mattress (he was in a toddler bed so the matress was a crib mattress), another sheet, then a third layer of mattress pad and sheet. When there'd be an accident in the night, instead of having to change the entire bed, I'd strip off a layer, replace the blanket if needed and we'd be back in bed in no time. I'd leave the bedding if only wet in the bathtub and deal with it in the morning.
We finally "got" the night time thing eventually. One night after bath as I was putting on his diaper he said that he didn't want to wear it anymore. We talked that he'd have to get up and go potty at night on his own and he said he would. So we stopped beverages at about 6:00 pm ish (we didn't do drinks before bed anyway- another one of those things we figures we'd have to change later if we allowed it to start when they were babies in diapers), he'd use the potty before bath, wear his pants to bed, hubby and I would wake him up at about 10:30 when we went to bed, he'd go potty, and I'd set the alarm to get up about 3:00 am (knowing it was just a temporary thing to get up nightly at 3:00 am!) to walk him to the bathroom for a final potty break. Once he stopped really showing me he had to go at 3:00, we'd just leave him sleep through the night. I think the night time thing took about a week before he'd be consistently dry all the time, all night on his own.
Whatever you do, you can't become stressed about it. Seeing or feeling your stress will make it so much harder on both of you. Yes, you're gonna have wet/soiled underpants to clean. Yes, it's an inconvenience to go anywhere while in the process so be prepared. Imagine, though, that there weren't any diapered Kindergarteners- eventually it will happen. SOme are quicker to catch on, some aren't. Some start out really well, then stop. You have to let him think he's in control- give him plenty of options (Do you want to wear the green underware or the blue ones? Do you want a sticker when you go on the potty or an M&M? ) Those mindless decisions empower them to think they're really in charge and they can do it.
Wow- sorry for the novel! I hope there's something that will help get going in all of that!