many ways to do this, this's maybe the simplest way okay these things you have to prepare before here i used Corel Draw X4 and Photoshop CS4 and prepare the photo which you'll manipulate
example i'll use this photo
and now open COREL DRAW and create any tatto model you want e.g
consider the pixel and size of your photo and corel pixel
Then - OPEN your photo with Photoshop
eg.
THIS is the trick
look at your CorelDraw THEN DRAG YOUR TATTO (make sure your tatto is one object/ grouped)
DRAG...