Ok, that is not exactly a frequently asked question, as I claim, but…well…it should be! There are way too many accidentally out of focus pictures out there. Out of focus can be cool, sure, but only if it is on purpose. Some of the great photographers had out of focus shots, but that was for very different reasons.
The basic problem is that most cameras are set, by default, to a multiple focus point setting, meaning, a pathetic, little computer in your camera is deciding what in the scene needs to be in focus. I personally think my brain is a bit more sophisticated than my camera, and I would much rather choose for myself what is in focus. So, here is how I do that.