The way I remember this is something I learned back in grade school. Remember your neighbor ROY G BIV? Red, Orange, Yellow, Green, Blue, Indigo, Violet. Deer see the best in the back part of this spectrum. They actually see blue, indigo, and violet very, very, well. As far as the first part...red, orange, yeller, and gree...Not so much. That's why I don't get so bent out of shape by wearing blaze orange. Lots of hunters try to minimize the amount of orange that they wear, thinking that the deer will see this bright color and run away. This is wrong. They don't see it at all hardly, and if you have colors that match, it'll blend into the environment for the most part.
Great first question, and welcome to the forum!