Smiling Girl

Well, this one turned out quite good. I like the strong colours - red and blue. The right head of her head looks a bit weird, there should be more hair...
Now, this clearly steps away from the manga style as I know it. This looks more like a traditional drawing of some sorts.

Cartoon and manga have very similar characteristics. The main differences for me are the proportions - which you seem to have quite well done in this one, there is no overly cute, round shaped head, the eyes seem to have the right size etc. - and the shading! Manga may have gradients and several layers of shading, cartoon shading is usually done in only one step. Here's a Link (see what I did there?^^) to show you what I mean. This is a simple, clearly outlined, high contrast shading, only that it's not black, but simply a bit darker than the rest (high contrast shading in black is generally used for other styles). This is partly due to the medium. Most cartoons are digital. Adding an extra layer with only the parts you want shaded in black with lower opacity is quite easy.

Keep your colours simple. Only one base colour for each area. Skin: one colour. Hair: one colour (you can add more areas in the hair if you want more colours). One piece of clothing: one colour (buttons, patches etc. can have their own area). If you use gradients, they should be subtle.

Another thing that you will see with cartoons is outlines with varying thickness. Another example. The cartoon effect is stronger if you use black lines, but sometimes, especially with a good background, it's better to choose a darker shade of the colour it's neighbouring. Go from this to this.

Oh, and cartoons like to exaggerate. Not everyone likes that, but if it's what you like... (from this to this)

This comment was made on behalf of for their 52 Week Comment Challenge.