This “wild color” effect is incredibly popular right now, in fact there are entire collections of royalty-free stock photos that use this technique, and you see it used often in print ads, for photos supporting articles in magazines, and on the Web. It's ideal for taking an otherwise boring image (like the dull phone photo used in this example), and using wild color to make it trendy and interesting.
Quick Tip: Stroking Path shortcut
Got a Path? Want to stroke it with a Brush? You do? Great! Just pick your brush, press the Return (PC: Enter) key, and Photoshop will stroke that path quick like a bunny (that's hi-tech talk).
Open the photo you want to apply the effect to. In this case, it's a regular RGB photo ...