Started with my DS2 (now nearly 17 months) about 2 months ago. He doesn't actually sit on the step, but in the corner next to the chair and sofa.....doesn't stay long but he HATES it so seems to be working
I started when my ds1 was about 18 months old - but he was familiar with concept from childminders where she did it for the older kids. Still use it for him and he is nearly 7 and for ds2 age 3.
Apparently it is one minute for every year of a child life. So for a 2 year old no more than 2 mins on the stair.
We use the naughty step, started when DD was about 20 months old. Works well but we have to close all the doors off the hall and leave her to it for the couple of minutes when she's on the step or else she just keeps getting up.
Have to confesss I've never bothered with the 'minutes' thing. For DS1 4 minutes is no where NEAR long enough - usually at least 10 minutes, and if he keeps on (which he does sometimes) he's been known to spend up to 1hr in the naughty room! (thankfully doesn't happen very often)
Tried it last week with ds2 (2) but he just kept getting up. I kept telling him he had to say sorry before he got up so he was there for over an hour and only came off in the end cos tea was ready - did I do it all wrong then? 2 minutes on the stair for crayoning on the wall doesn't seem like much to me.
gobble - TBH I don't think there is a 'right' and 'wrong' way to do things like that. The best we can do is what works for US and OUR children, I firmly believe that consistancy is the key and as long as you're consistent then you're being fair
I introduced the naughty step at age 2 for my DD. It was a bit of a nightmare at first to get her to stay on the step and it took alot of barracading of the lounge door to keep her on it. However it has been a successful and she is now less likely to push her luck. She is a yr older now and the threat of it is often enough to get her to do as she is told!