In reply to @soupie66
@soupie66 don't just use colour. In visual things you can use patterns as well (or instead), and in text you can give other information, e.g. instead of "the red circle" say "the red circle at the top-left"
In reply to @christianp
@soupie66 don't change the colour of text to bring attention to things. The number of times I've missed important information because it's "highlighted" in red!