step1: i open photoshop ( i've used photoshop cs5 but i could have done the same things in the previous versions ) and then i plugged my wacom tablet ,and start making the rough as you can see it on the picture below. it was quite easy and fast.
step2: i've created a new layer on the top of the last one ,basing on the rough i've drawn the line art and now i can hide the rough's layer.
step3: i've created a new layer below the line art and start my putting colours with the brush tool . this tool is quite helpful when one use wacom tablet
step4: i let my inpiration guide me , no more hand drawing i've used photoshop's tools do the rest for me.