Thanks Pale Horse for your great tutorial, I am a big fan of your works and I was really excited when I found this amazing site.
Here's my sketch...
The line art...

Colors...

t-shirt...

Hi!
I tried another one from a different photo reference...
line art...

colors...

t-shirt...

Hi!
Here's my third skull



Hi!
Here's another version with different background as suggested by Trey Eckles,
I prefer this one,the skull stands out better, the green splat on the previous was a bit distracting.
