I forgot where i found the source of the similar image come from
But it's in my anime wallpaper collection files since long time ago.
I just desaturate to remove the original color, add more b/w contrast, erase some parts, resize and placed to fit in your picture.
Of course some finishing parts must done by adding manually with editor brushes .hardwork.
...but that is the fun parts when my limited drawing knowledge actually become handy .nerd.
@Mr.Suzuki: good picture, specially the "shading" is awesome