I used to doubt the effect of consistency with kids. After I have been practicing for a while, it really works like a miracle. I have been using the consistency with sleep training, goodbye hug/kiss, and dining time.
Sleep training is really hard for everyone. We started sleep training when our kid was 10 months old. He definitely cried. But we have been consistent with the routine, picking up him, comforting him, and putting him back into bed again. It took two weeks for him to understand the routine. Nowadays, he still cries sometime when it is bedtime. While I turn off all the lights, he walks into his room pretending to cry. He will ask for mom to pat him and stop crying in less than 1 minutes.
I used to sneak out to avoid to see my son crying. After I read some books, I started to say goodbye to him when I leave him. He cried for sure, but I kept doing it and also explained to him why I was leaving and when I would come back. One day, when I was leaving, he smiled and said "bye bye mommy, have fun!". It is really sweet.
Keeping consistent and respecting the children are the keys for successful and easy parenting. The little kids are very smart and more capable than what we have imagined. Just being patient. Sometime it takes a few days for you to see the effects. Sometime it may take months. Treat your kids with respects and consistency, you will get back the same thing.
Books recommended:
Parenting Your Smart Underachiever With Consistency and Love: http://goo.gl/Cwqob5
Marva Collin's Way: http://goo.gl/XII6Qf