This morning Ella woke up and went pee pee on the potty, so I asked her if she wanted to wear her "big girl panties" today. She said yes and we started with a pair that had Dora on them. Approximately 30 seconds later, she wet them and did not like how it felt. She came right over to me to tell me that she peed in them and she wanted them off. The second pair she picked out had Elmo on them. She wore them all morning and until nap time without an accident. We would ask her where she is supposed to go pee pee and she would tell us "in the potty". We sang songs about it and put her on the potty often. For nap time I decided to put her in a pull up, but she wanted her big girl panties on also.
It's just the first day, but I think that it's been a successful start. Here are some pictures of her wearing her new big girl panties and her snow boots (she had to have the boots on), and one with her Dora slippers on: