You know how it goes, you compose a great shot
while out with your camera, but when you get the image onto your computer your
eye is drawn to some distracting highlights in the background.
So, before you press the shutter, how can you eliminate or reduce the impact of
such distractions?
Among your options are to change your camera angle, shoot at your widest aperture, remove the distraction before shooting, remove it in Photoshop, or as I like to do,
'darken' the background. This can be done with a piece of dark cloth placed as far back as possible from the subject - a dark colored coat works too - or by casting a shadow on the busy
sun-lit background.
The latter method was used below for this pair of before and after samples. In image 1 the background has multiple light-colored distractions. So, before firing off image 2 I positioned my body such that I was casting a shadow behind the subject . . .

Image 1: Normal
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Image 2: With a shadow was cast onto the background
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Teasel on the Palouse, Idaho: Both images were exposed at 250th @ f.8
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I assume that you can observe that image 2 is the superior of the two, but had I created a completely black background,
i.e. high contrast, it would have been really, really stunning!
Here are additional examples whereby a dark, uncluttered
background adds to the impact of an image . . .

Sheep's wool on a wire fence, Wales.

Sheep's wool on a wire fence, Wales, with a slight change of
camera angle.
I thought the background of the top wool image was colorful but a bit bland and lacking
depth. To fix that I changed my camera angle so that bottom image of the two
gained a dark background, and 'interesting' soft out of focus points of light.

Spider's web on Sheep's Bridge, McCall, Idaho. I lined up the web
with the shaded river bank to achieve the dark background.

Shrub, Iguazu Falls, Brazil |

Grass, Grand Teton national park, Wyoming. |
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As you may have gathered, the darker the background, the
greater the impact. It also needs to be stated that backlighting is a factor with
each of these images too! 
Remember that whatever you photograph, the end result is limited only by your imagination!