Highlight Mail from a Sender With a Color in IncrediMail

We've already learned how to Spring-clean today. But Spring is not only clean, it is also green. And Winter is white, Summer is blue, Fall is red. Yes, nature color-codes the seasons (where they exist) so that fauna and flora know what to do...
Bob is yellow in my IncrediMail, Chris is orange, but you are red. Here's how to have IncrediMail mark messages from a sender with a color automatically.