Thank you Andy & Corey. The link is too helpful. And for the lighting I used V ray sun and the Vray sky and enabled the GI. I attached my settings and the image after rendering, and for the post processing I followed the tutorial http://cg.tutsplus.com/tutorials/chaos-group-vray/compositing-v-ray-render-layers-in-photoshop/. any suggestions for my settings and what things should I consider in post process?