I agree with madb about readiness...all kids are different and perhaps she isn't ready. Tbh the fact she still wees at nap time indicates she can't control her bladder yet. Dd was dry during naps and could hold for long periods before I started tt (and at two and a half could go twelve plus hours between toilet trips, day or night...which even I can't do!).

I would try getting her to wear no pants for a period of time each day (ie when you're home) and tell her when she feels wee coming in her tummy to run to the toilet. I demonstrated this to dd, and for some reason the running and yelling wee wee was appealing then lots of praise etc.

I would avoid treats and stickers until she gets the general idea, because it sounds like it's just confusing her, and she needs to understand the concept of holding until she is on the loo.

Good luck!