How to use custom shapes with the Photoshop blending modes such as darken, difference, lighten etc
Select the CSH tool and set the option to 'layer' and then add the layer with the current design (or select another). You can then go to the layer panel and select the blending mode as well as the opacity - set them to darken and difference and the result will modify how the artwork interacts with the underlying layer. You can modify this at any point as well as change the color and the stroke of the vector. You can repeat this with new vectors to build all kinds of images.
Some blending modes are better than others and work well with some color, with other colors you will see no change at all such as trying to use the lighter color with a light image. Adjacent you can see the same vector (splat frame) added over and over as layers and with blend including difference and darken and lighten and so on.
The original source artwork can be found in the 13,000 Photoshop shapes collection) You can also find many other shapes sets on the site such as rosette / flower custom shapes and a lovely set of scratchy and doodle and distress custom shapes and super sharp saw blades custom shapes for Photoshop and elements
You can do the same as above with the pixel option for the vector CSH artworks but the big difference is that you have to change the mode each and every time you add the custom shapes and the result of the shapes and the blending mode is destructive so you can only undo to change the result. Once advantage of the pixel mode is that you can use the fade to retrospectively change the mode.
The adjacent image uses a blending mode of overlay with a color of blue custom shape added to a pink and dark red background. All kinds of color combinations can be created using just overlay but you also have many others (and some applications such as Affinity Photo have many more and it would be a lovely thing to see in Photoshop CC 2018 more blending modes for custom shapes as well as layers etc). Right, you can see the result of a blending mode of overlay initially applied and then using the edit menu and fade command the blending mode for the custom shape was changed to difference to create a different color effect.
You can, of course, add the custom shapes (the example shows a rectangle for simplicity sake but it can be an oval or ellipse or custom shape etc in Photoshop) again and again to create all kinds of color combinations using the blending modes (changing them via the fade or via the blending mode dropdown in Photoshop). Below, you can see multiple applications in difference mode of a simple rectangle shape. You can keep the color the same or vary the color to create even more extreme color combinations in Photoshop
linear dodge (add)
You can find other tutorials such as using how to use custom shapes with image modes and how to use the shapes with the palette / panel options and how to create animal custom shapes using Poser / Illustrator / Photoshop and how to add a glow to a custom shape in Photoshop tutorial