Style categories in WordPress

I have a WordPress site with about 200 categories. Now I would love to be able to style every one of them by adding a image, feed and some text.

Something like this, just above my entries:
https://pici.se/pictures/ovHAbfJli.png

I tried adding a long PHP file with about 200 switch, but this only resulted in the page going blank. Therefore I’m wondering if you have any idea on how I can do it, or maybe if there is a plugin for this?