Fix articles with poor grammar and inconsistent grammar
Make minor edits to make the tone more consistent
Find sources to back up claims. If I cannot, I'll add citation needed.
Upload images/videos to the commons to clarify what an article is talking about
Create userboxes
I also draw and I might upload some stuff to the commons, sometimes as an example for an article, but it'll usually be explicitly just for my user page. I only post my art to the articles if I felt like it needed more examples, not to be promotional. It is completely fine to remove it if it does not suit the article well, or if there are already enough examples and I did not realize.
Examples:
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