This is easy yet hard if you can believe I spent 5 hours sitting here working on the skull straight no breaks. I use a mixture of Autodesk's sketch book pro and Photoshop cs6 to complete this tutorial, however you only need one of the programs. The reason behind using both programs was merely my preference i find that I can sketch way better in sketch book pro then I can every in Photoshop, but I prefer to do line art inside and coloring in Photoshop. Included with this ible is the .psd, the back ground, and the texture you need.
Please feel free to ask any and all questions I will gladly answer them.
Step 1: The Sketching Process
The size of the document doesn't matter. To begin I open up a blank sheet in sketch book pro then change the back ground layer to black then picking a neon-ish blue and begin to work on a new layer above the background. Starting with the outline then the inside with the bigger features trying to figure out spacing moving into the smaller features then. Choosing between black or white to sketch on is a personnel choice i prefer to sketch on black then change back to white for line art. Also note I use a number 2B pencil to sketch.