Setting a colored layer to exclusion can do great things to an image. It's mostly used for altering the color of an image, and depending on the color that you use on the exclusion layer and the colors in the image itself, you'll end up with very different effects. Here are some examples of how to use an exclusion layer.

Here's our base image:

Usually, a dark and intense color works best. It gives subtle change to the image but enough for a nice effect.

Using #001756:

Using #00433A:

Using #4A2D00:

Using #5C0000:

Using #590054:

If you use a medium color in between the dark and light range, your picture will look very dull. I hardly use this effect myself, but it might be helpful if you're going for a muted look.

Using #005A88:

You'll find that if you use a color that's too light, you'll end up with an ugly inverted color scheme, like so:

Using #FFE0B0:

However! Create a new layer between your base image and the exclusion layer. Fill it with a different pastel color, and set it to difference. This gives you a beautiful duotone effect. There are so many different color combinations you can make here - the possibilities are endless!

Using #FFE0B0 on exclusion, #F7CBFF on difference:

Using #CBFFF8 on exclusion, #FFFCCB on difference:

Using #FFE0E6 on exclusion, #FFF4DB on difference:

Remember, depending on the colors and darkness of your base image, the exclusion layer will give you different effects. It won't always look good on all images. This effect is heavily dependent on experimentation, so go wild with the colors and see what you can come up with!