As my manga drawing skills aren't up to scratch, I've been practicing while on the train in my sketchbook. Normally a manga artist would sketch the outlines to a scene/character on paper then fineline using a thin black pen.
I have neither the space, skill, paper or tools to do this... so to get my sketching up to grade I'm copying stills from anime's and shading them in for effect. Mayu above is an example of this; if I had more time it would be worth tracing this and applying the correct colour palette (I'm sure it'd look ace then...) but for now its a good progress piece.