I mostly contribute those high-quality screenshot things. Most of how I go about that was influenced by how I was told to do it on RuneScape Wiki, so I might need extra pointers here and there, like how new files are actually uploaded and replaced in articles as opposed to just uploading new versions of images on top of the old ones since episode mumbers and that shizz is factored in, since there's sysop hullaballoo for file re-naming and file re-linking across articles and you know.
I compress my PNG contributions with this tool , which I also retained from my time on RuneScape Wiki.
Otherwise I mostly make those vector things you may have/have not seen.
I also like Flash Sentry. Take that as you will.