I know my child's a different sex, but DH took him to the toilet when he went, so he could see how it was done... Maybe take your DD with you? Say "big girl's wee's " (we used to tell DS to do big boy's wee's like daddy, he idolises his dad) we also used the sticker system, but every 5 stickers they got a treat (we used to keep a 20 pack of freddo's handy, every 5 stickers he would get one.)

Hope this helps, im going to start getting my 20 month old ready for toilet traingin this summer (dont expect it to happen until next year though!!)

Good luck!!