I started officially a month ago with my toddler. He will be 22 months on the 3rd.
As for knowing he was ready, he showed a lot of interest in the toilet, wanting to go with DH and me when we went in the bathroom, and hiding when he was pooping in his diaper. He also started taking his diaper off.
He still doesn't say that he has to go but 90% of the time that he is home I get him to the toilet in time to pee and 100% of the time to poop. He loves flushing the toilet afterwards and watching the water swish around down the drain.
I didnt start at any particular time. I also let the kids decide w.out my influence.
K decided 2 months before she was 3 that she was a big girl and that was that, she didnt even wear anything to bed because she was just ready.
M started potty training the week of Thanksgiving 2011 (23 months) and JUST in the past 6ish weeks is fully day time potty trained. She still wears a diaper to naps and bed because she pees niagara falls. She hasnt had a poopy diaper since last year thank goodness, she has done that on the potty from the first time she used the toilet.
my daughter is 18 months and she always follows me to bathroom and watces more and sometimes acts like she is wiping and also starting to take her diapers off and i believe she is holding her pee. im changing 2 wet diapers a day. we have appt. at childrens with urologist just in case its something else