About 2 weeks, get a little book and each time they go on the potty they get a sticker, page per day that way they can see how many times they go, first couple of days is a nightmare my first daughter pee’ed about 12 pairs of pants, she got it pretty quick though, waited till I was on holiday from work to start it so that I could constantly remind her to go, we’ve used the book and sticker method with all 3 daughter with great success, as the days go on they you can see via the number of stickers per day their control getting better, good luck,
PJ