needs a lot of work. The edges are very rough. Also it's very basic with very basic shadows.

Overall, not very good, but, you need to work hard on this technique.

There are many more points, but, i don't the time to get detailed.

Your lines are very rough. I would suggest drawing in Illustrator.

The outline of the bow needs a lot of work. It's very poorly drawn.

I would suggest keeping your outline on a separate layer from your coloring.
And keeping every object you color on a separate layer (the chest one layer, the diamonds another layer, the bow another layer, the shirt another layer).

You also should have colored the box the same as the rest. Consistency is key.
You have it a weird texture, that doesn't match the rest of the image.

You have the lighting on the characters coming directly from the left, but then threw a sun in the top right?
Also, putting a sun in the corner like that, is very amateur-ish. That's how children draw suns.

Work on lighting and shading.