Using the potty is an important milestone for your little girl, but you need to use the correct methods of teaching. Due to the different genitalia, teaching girls to use the potty is a bit different than teaching boys. Remember that each child will learn to use the potty at her own pace and you could do more harm than good by pressuring her to use the potty or disciplining her after an accident. Take things slowly and you'll eventually reach potty success.
Purchase a small potty or two. Take your daughter to the store to let her pick out the potty that she wants. Some are pink or have a princess theme while others are more gender neutral. Since they're usually fairly inexpensive, it can be smart to buy two or three so that you can place them in different rooms of the house, avoiding potential accidents because she'll be able to get to the potty faster.
Decide on training pants or pull-ups. Pull-ups are like diapers except that she can pull them up the same way that she'd pull up underwear. They prevent any accidents from leaking onto your couch, but can sometimes too closely mimic a diaper, letting her feel that she can go whenever she wants. Training pants are thick underwear. If she has an accident, she'll be able to feel it, but you may be doing a lot of laundry. Some parents choose to let their children wear no underwear at all.
Put her in dresses for potty training. This makes it easy to get on the potty quickly, without having to worry about buttons or snaps.
Teach her the proper way to sit on the potty. She should sit with her legs toward the front to avoid spraying.
Sit her on the potty at regular intervals. At first, she won't know when she has to go, so you just have to do it once every hour or 30 minutes. After awhile, she will recognize the signs that she has to go and sit on it herself.
Reward her for good behavior. Give her a treat for sitting on the potty, for going pee and for going poop, with each reward a little bit "better." Consider rewards that will make her feel motivated. For example, you could give her a single candy for sitting, a few for urinating and a new doll the first time she has a bowel movement.