Here's a quick little tutorial for adding/changing the color of your photos.
Select the photo you want manipulate and open it in Photoshop. Make a new Layer.
Find the small black and white circle icon at the bottom of the toolbar.
Select the Photo Filter option.
From the drop-down menu, select the color you want use.
Using the density slider adjust your photo until you're satisfied.
Save and enjoy!
For more tutorials click here and here.