This is a technique called texturizing. There are so many ways to do this, so much that my head spins. Basically I used 3 layers, but most people use only two.

The bottom most layer (L1)is the background layer ie the leaf. Then the main subject, Sofea, is the second layer (L2). This is followed by another layer (L3) of the leaf again. Using a variety of blending modes and adjusting the opacity/fill, you can get a final images like the one here.

L1 is usually set to normal mode at 100% opacity. L2 (Sofea)is again at normal mode but the opacity set to around 80-90 %. Some people like to change the blending to multiply. The third layer, L3 is usually set to multiply with the opacity around 12 to 20%. These modes and amount of opacity must be tuned to suit your personal tastes - no hard and fast rules here. Other additions can be added eg layer styles like drop shadows, beveling etc.

Do note a lot of had to be done to the oringinal L2 layer (the main subject). Usually this involes erasing all un-necessary background and a bit of feathering.

Needless to say the choice of background is extremely vital - a wrong choice can kill the image.