How to get a clear focus in photography?

I think there are many similarities between photography and target shooting, as you asked in your question: how to get a clear focus in photography? The focus is right, just like whether the target can be hit correctly. Nowadays, digital cameras are very smart in focusing, and many means can help to observe whether the focus is clear. For example, when shooting a distant target, if you can't accept autofocus, you can choose manual focusing, carefully observe whether the target picture in the focus frame is clear, and slowly turn the focus ring on the lens until you find the best focus.