Save the file also. SAVE- you name the file. Now you are safe if something unspeakable happens. On The Bone Layer, fill in the selection area with a pale white color by selecting a foreground color and doing a fill. Time for some surface effects.
Most bones are dirty from earth, blood and other things.
Choose your dark and light colors for the effect, and then apply the filter of your choice. In this exercise I will use EC's Smoke filter. Then Blur the bone layer with gaussian blur. If your image is as light as mine is at this point, go ahead and change the color balance to make it darker and more yellow. Then Add a dark lower shadow along the bottom of the bone with a wide fluffy black brush, around 45 or 64 is good.