The best way for you to start is to spend time reading in the Gentle Discipline forum. You can also check out my site at
www.aolff.org. There's a reading list in the FAQ for the GD forum.
This site is against punishment--not just spanking--so the answer isn't finding other things that make them miserable
There is no reason to try and make a child suffer as though that is the only way they can learn.
ETA: Discipline means to teach . . . so you teach.