Here’s a quick trick to add a bold color into your monochrome effects. In Photoshop, click the Create Adjustment Layer icon and choose Curves. Double-click the white eyedropper icon in the Curves box to open a color box. Choose a bold color, then click OK (don’t save as defaults). Now click on a highlight in the image to add the color to the highlight tones of the image. It works best with high-contrast images like this.