Your shading is very messy. Spamming light and dark pixels everywhere makes the skin look poor and gives the impression that you haven't put any effort into it. Also hue-shifting is very helpful, I'm sure there is a blog explaining it somewhere.
When we have 20 people who have entered the competition, there will be a theme every week for 4 weeks. For example, if the theme is "Disney" you would have to make a Disney themed skin c:
