The great thing about Photoshop is there are almost always several ways to accomplish the same result.
The bad thing about Photoshop is we often get confused with all the different ways there are to accomplish the same result.
One technique that often makes good pictures better is turning your digital colored photos into Black & White images.
"Why do that," you ask?
Sometimes, the many different colors or patterns in a photo distract from the overall appearance. Or, sometimes you want to feature only one particular aspect of a scene - and that can be done with selective color. That's accomplished when you turn the original image to black & white and then allow only your chosen feature(s) to be in color.
Here is a reminder of the most popular ways to turn a colored image to black & white:
Image - Adjustments - Desaturate
Image - Adjustments - Gradient Map (preferred for preserving details) be sure palette set to default B/W
Image - Mode - Grayscale
Image - Adjustments - Threshold (absolute black or white, no grayscale here)
Layer - New Adjustment Layer - Hue/Saturation (move saturation slider max. left) good for selective color by later using layer mask to bring areas back to color
and for the more artistic look...
Filter - Sketch - Chrome
Filter - Sketch - Conte Crayon
Filter - Sketch - Graphic Pen
Filter - Sketch - Halftone Pattern
So next time you've feel the need to go Black and White, plan a few extra moments to try out something new.