Keeping an Eye on Your Subject
I see a lot of photographers who prepare well, do their research, and
get in the right place at the right time only to miss the shot. Why?
They got distracted and took their eye away from the viewfinder while their subject
proceeded to do something amazing.
Thankfully, there is an easy way to reduce the chance of this happening. Once you find your subject, take care of your metering and set your focus by pressing half way down on the shutter and wait while watching through the viewfinder. Once the moment of action comes, all you have to do is squeeze the shutter all the way and capture your image.