With our daughter, we made it a group effort. At this age, she got distracted by a lot of things that were far more interesting and would hold off going by herself and always had an accident.
So, as much of a pain as this is, I would always go with her and encourage her. I also would tell her to go and take her potty frequently throughout the day. Its a hassle, but she needed the reminder and the presence of a parent to enforce the behavior until she really got it.
When she had an accident, we'd tell her she had an accident. We wouldn't shame her, but we'd tell her she needed to go in the potty. Then we'd make her clean it up, change herself into something dry,and put her wet or dirty cloths into the wash.
When she was running to the bathroom regularly on her own, we gradually stopped going in there with her and we gradually stopped asking or telling her to go.
She still has the occasional accident if there is something really new or exciting going on, but she did get the hang of it.
As she became more aware of things and really understood her body signals, she came to hate wetting herself or soiling her underpants. It takes some practice and some recognition on her part though.
Keep working with your daughter. She'll get it.