My son (like many kids) has a HUGE independent side to him and wants to do everything himself. When I tried putting him on the potty or toilet he would resist and it always turn into a huge tantrum. I moved him into pull ups at age 2, and every now and then he would maybe try for a pee in the potty, but he was by no means consistent with it. Then he hit 3 and suddenly he could not only pee and poop on the toilet with no help, but could also wipe and wash his hands too! He was still peeing in his pull ups a couple times a day so I just put him in underwear and after 2 days he was fully trained. So it may have taken him a bit longer than some kids, but I avoided all the tantrums and he learned how to do it all himself very quickly. (Not saying I was being lazy with my parenting - but any mother of a very stubborn and independent child knows to pick your battles, and also, with some kids, pushing them into something that they just aren't ready for will only make them want to do what you are asking less.)
When starting on the potty or toilet, I would first look for signs that your child is about to go. They may tell you they have to pee, or maybe you see him/her make their "poop" face. When I saw that I would ask if he would like to try it on the potty. Also, when my son started going somewhere alone and private to do his business in his pull ups, I took that as a sign that he was ready.
I bought a wonderful kit from Chapter - The Potty Caddy. My son was so excited it really got him in gear to use the toilet. It was a box that contained: a guide for parents, a kids potty book (one of the funniest things I have ever read!!), a potty chart and stickers, flushable potty targets to aim at, kids magazines to read on the potty just like daddy, and a toilet paper holder in the box for his/her own toilet paper. Basically everything you need in a carry case that makes it fun for kids.