This very simple tutorial will show you how to turn this:



Into this:



First, take your picture and duplicate it. Next you need to set the bottom layer to Grayscale, the way i do this is go to Adjust >> Hue & Saturation >> Colorize

Then you need the same settings as this:



Next, set the top layer to 'hard light' like this:



That's it! You've improved your picture with this very simple tutorial :)