I selected some parts from a wodden circlet. Using the warp tool I shaped the selection to look like some monstrous arms. Colored arms to yellow (hue/saturation) and rendered natural shadows by desaturating them onto a new layer and changing blending mode to overlay.
Casted shadows for each element: collar, body, wings.
Added a fill linear gradient from black to transparent on the bottom part of image for general shadows and another one from yellow to transparent on the top left side of image for light.
Corrected some areas using the clone stamp tool and added a brightness & contrast adjustment layer.