Use of Color
Don't use color alone for meaning
Color is very useful for conveying meaning quickly, but you can't rely on it exclusively. Users with visual impairments (which includes blind, low-vision, and color blind users), can often have issues understanding if color is the only thing that differentiates information.
Take for example the following page that was on our old website:
The image on the right is the same exact page, but filtered to appear as if someone with a very common red-green color deficiency is viewing it. As you can tell, the information about what steps each person is required to do is lost. And this is just for a very common visual deficiency, let alone someone that was fully visually impaired.
There are many ways to solve this (for example, adding symbols such as ^ after each line). What we ended up with was slightly modified version of the page (below) which solves the problem by having the responsible party listed as part of a table.