Where do I start?

You wait until she shows you signs that she is ready. Potty training before a child is ready can be quite traumatic.

I potty trained my step daughter that I have 2 days a week, she picked it up really quickly. I set my alarm on my phone and every 10-15 minutes sat her on the toilet, whether she had to go or not. I also put her into dora pants not pull-ups cause she realised quicker that it was not nice to pee or poo in these. I gave her loads of trust, her granny will still put on pull-ups when she leaves the house with her and of course the baby does her business in them rather than going to the toilet. (It's there why not use it like)
Now all right I take about 3 out fits with me when we leave the house but I don't make it known to her and she NEVER has an accident with me at all.
Show her you trust her and that she is independent.

Hope that helps
Shauna