Both these ladies had very good suggestions! I did all of those with my son (letting him pick his own underwear, monkey see monkey do, etc).....At 15 months my son also showed signs that he was ready to be trained, and he even went on the potty a few times.....I also bought him the video "Once upon a Potty" (they have a boy and a girl version) and he watched that every day, at least 20 times a day! LOL...
15 months turned out to be too early for him though. Then I found out I was pregnant on his 2nd birthday, and shortly after I was getting so exhausted and tired of changing diapers. On a Saturday, I decided it was time to do some intensive potty training; every time he needed a diaper change, I'd tell him "you know, if you went on the potty we wouldn't need to change your diaper and you could keep playing" and I'd have him sit on the potty each time....and every time I went too...and I used star stickers and a potty success chart....the very same day he started actually going on his potty and we made a big fuss each time he did, gave him a star on his chart, watched the potty video, danced and sang.... it's been almost 2 weeks now and he hasn't worn a diaper since then....
Haha yesterday at the park he had to pee but didn't tell me; I saw him over in the grass pulling down his own pants to pee in the grass! Oh man everyone was cracking up!
Good luck to you and your daughter!! I hear girls are generally easier than boys to potty train....
Four of the most important things are:
1) Be consistent....if you slack off and allow her to take a break (wearing diapers for convenience) she can regress.
2) Remember to give her lots of praise, even if she only sits on it and doesn't go. It will encourage her to do it again.
3) If she has an accident, don't make her feel embarrassed or badly about it....that can make her not want to tell you that she needs to go, slowing down the process.
4) Don't get frustrated, she will pick up on it and she will get frustrated as well.