Tip #56: Isolate Your Subject
Keep it clean. Avoid distractions. Isolate your subject. Tighten up the shot. Keep it simple.
There are a number of ways to say it but they all mean the same thing: keep that photo free of distractions by isolating your subject in the image. This may mean zooming in tighter or changing up the background so that there are no distractions to move a viewer's eye away from the main subject. This will make the subject really stand out and clearly communicate a story.
Growing up I had a friend that always told me a great acronym for a variety of situations: K.I.S.S. It stands for Keep It Simple Stupid. It applies well for this tip.
Another more famous variation on the same theme is the quote from novelist Henry James, who said, "In art, economy is always best."
So when composing your picture - ideally when taking the photo to avoid loss of pixels rather than cropping in post-processing - avoid too much in your shot.
There are lots of ways to do this - from zooming in to physically moving closer to your subject to changing the camera settings for shallow depth of field - but which way you choose will depend on the story you want to tell with your photo and how you want to best present the subject.