http://www.dgtouch.com/photo-retouch/
Follow a few of these to learn different techniques, and then put your creativity to work and find some ways to use lighting effects, resizing shape and remove a blurred or smeared mark on the surface of something on your own.
Read more at http://www.dgtouch.com/
photoshop
photoediting
graphicdesign
productretouch
dgtouch
photoretouch
imageretouch