Join Date: Jan 2008
Posts: 7,248
Don't use only one size for every situation.
When choosing your sizings, consider what you're trying to accomplish, what your opponents range is, how you think he'll react to different sizings, and choose what you think is best.
To get good at this you'll have to spend a lot of time playing and studying while thinking deeply. After some time you'll get good at doing it quickly.