Ah yes potty training...one of the many joys of parenting.
We trained our son when he was 2 years and 3 months old. We did it non-stop for a week, tag teamed it...my husband is more patient than me. We had some major accidents, and you will continue to have some minor ones after they are trained. Our son just turned 3 and peed his pants yesterday for no apparent reason...and lied saying he didn't have to pee when he was on the potty. I tell people to LEAVE him there at least 5-10 minutes, sing, tell stories to distract them and he will go.
Our son likes to hold it to the last possible second. So I monitor how much liquid he's intaking...and make sure he goes every 2 hours even if he doesn't tell me, which they won't always tell you.
In the beginning with training him, I started in the bathroom, but then he was stubborn not wanting to go...after 30 minutes in the bathroom I would get frustrated. It was a battle of the wills...so I moved his portable potty to the kitchen tile floor in front of the TV...and made him sit there til he went.
Then it seemed to stick and he got the message of going in the potty. After that we had to watch him like crazy. If he starts doing the dance we scoop him up and run him to the bathroom, no questions or negotiating. And we make him sit there until he goes...remember he's stubborn.
As for night time we cut off the liquids 2-3 hours before bed. Make him pee before going to sleep. And then after he's been sleeping about 3 hours one of us takes him to the bathroom in the middle of the night, we don't say anything or wake him up, just sit him on the toilet. If we take him in the middle of the night, then he wakes up dry.
I refused to buy pull-ups/diapers so once we trained him, there were no more diapers. I heard stories of people training and then putting diapers on...it confuses them. Or my friend put the diaper/pull up on at night to avoid wet sheets...her son held the poop all day until that pull-up/diaper went on and then released it.
Good luck. It gets better with time, I promise. Be sure to always keep a spare set of clothes with you for unplanned accidents.