I am not sure if you are using pull ups or not, but I would almost suspect you are? If so, ditch them first off and just go to undies only!
With pottying it is basically just being consistent and making it be the child's responsibility. By this I mean you have to be the one to take her in regularly and expect her to use the potty, but only she can actually go in it. By her age, unless there are delays somewhere, she is perfectly capable of getting this.
I would start of by watching the clock or setting a timer for about every 30- 45 minutes. When it goes off TELL, don't ask, her it is time to go to the potty. Take her in there, but have her get her pants down and get up to the potty and go. If she tells you she doesn't have to go tell her that's fine but she is going to just give it a try to see if there is anything in there anyway.
If she does go tell her good job, but I wuoldn't make too big of a deal out of it since it really an expectation to go potty at this age and I'm sure you have been doing this in the past when she first was learning to get it. Now she just needs to see you mean business with this potty thing!
If she doesn't go tell her that's fine she can try again later. Let her know if she feels like she has to go potty she can go in, otherwise you will remind her agian when the timer goes off. In the mean time, there will be accidents! Another BIG part of them taking the responsibility for this potty thing is making them responsible for the messes!! If she has an accident SHE needs to clean it up (with your assistance if needed), as much as she can do! She can remove her own clothes and put them where they need to go, she can use a washcloth or wipey to clean up her legs and bottom, she can put on her dry undies and pants/ dress/ skirt/ whatever, and she can wash up the floor and her hands! It becomes more of a deal when it is her own job to take of it. Stand on the side as a guide as much as you can so that SHE can own it!
The pooping thing is a harder issue, hopefully with all the time she is going in she will just catch it, but this is harder for some kids. I would still have her do as much of the cleaning as you can handle, just be sure to wash hands. Poop is just harder to deal with, it will take more assistance from you. I would also recommend finding SOMETHING that will entice her. My BFF had to completely take away her daughter's chocolate milk until she would poop on the potty. After a couple days of not getting any while her brother did worked wonders for her! So you will have to find that "wonder" for your daughter.
Sorry this is so long, I just wanted to be thorough! She will get, there is a light at the end of the tunnel!!