Step 5
Once on the beach image, drag the new layer underneath the beach layer. Now hit CRTL+T to enter transform mode and scale/rotate/move to where you want it, but don’t make it bigger or you will lose quality.
Step 6
Here I have taken a different piece of rock and done the same thing.
Step 7
And again.
Step 8
One more time for good measure. Experiment by moving the pieces of rock around to get the best fit possible.
Step 9
Once you are happy with the rocks, highlight the rock layer just under the beach layer and hit CRTL+E. This merges the two rock layers. Do it a couple more times so that all the rock is on one layer.