I've trained four children. This is how I do it and it typically works in a few days.
Get the necessary supplies:
Potty chair or seat for the toilet
teri cloth panties
juice to fill sippy cups
coloring books, movies, games...
carpet cleaner
Start the first day in a bathroom or enclosed area with linoleum if you have one. Strip you little one naked and let her play like that. Entertain her and keep giving her the juice. She will pee pee on herself and when you see it happening hurry up and sit her on the potty. It usually only takes one or two times and they figure it out.
When you feel confident that she knows now what pee pee is all about..put some cloth panites on her (don't use pull-ups they are glorified diapers and kids just go in them...I've seen four and five year olds still trying to train because mommy used pull-ups).
Remind her every 15 minutes or so not to pee pee in her new big girl panties. If she manages to make it to the potty and get any pee pee in there...give her one chocolate chip or an m&m. You may need to set the timer to remind yourself to remind her.
It won't take long before she figures in out. Maybe even let her pick out her own big girl panties at this point.
You won't get much done for about a week, but she will train.
Poopies are a little harder. You have to watch the signs of straining and so forth. Often kids will freak out about it. They will try to go in their pants rather than sit on the potty. Make her sit. She won't be traumatized. If she does start to hold it so she only goes at night in her diaper (I had one smart cookie do that) give her a tsp of flax seed in some yogurt and a handful of mini shredded wheats each morning early. She will have to go before you know it. Don't give her a pull-up to go stand in a corner like I've seen some mom's do. They aren't going to be traumatized if you make them sit on the potty.
If you see her straining or hiding to go quick make her sit on the potty. If she cries, then just hold her and hug her and keep telling her that it will be fine. She will go eventually and then figure out it is fine like you said.
If she gets stubborn like I've seen some kids do..mostly boys. But the last one I trained tried this. She pooped in her pull-up that mom sent her in before I could put her panties on. She then told me she didn't need panties because she already pooped. So I put her in the tub with a bag and some diaper wipes and I told her that she had to clean herself up. She was surprised and thought I was kidding. I told her no. I didn't make the poop or the mess and I wasn't going to clean it up. I then gently showed her how to clean herself and put the wipes in the bag with the pull-up and I kept pointing out to her how disgusting it was.
She never pooped in her pull-up again and she was trained that day.
It really works. I have a five year old and a three year old that have been trained since they were 2 1/2 and then I trained my neighbors daughter when she was 19 months. They all go on the potty by themselves and haven't had any ill effects from being made to sit on the potty, clean up a mess, and so on. I'm always gentle about it, but firm that they have to go on the potty.
Good luck!!!