When you are trying to hide, remember the four S's. Shape, Shine, Silhouette, and Shadow. Notice that "Color" isn't one of the categories, as long as you are using earth tones you should be just fine. You aren't trying to fool the environment, you are trying to fool the brain of someone observing the environment. You want to seem so in place that you aren't "out of place".
Your eye will notice movement before shape, shape before silhouette, and silhouette before color. There are exceptions, such as a blaze orange hunting vest. Things that are designed to be seen usually work because they are automatically "out of place".
But when you are trying to blend in you don't want to have geometric shapes such as round optic lenses in the open. You'll want to dull anything that is reflective such as exposed skin, or metal surfaces. Break up your silhouette by having a few bushes between you and the area you are observing, or incorporate natural vegetation to break up the edges. Finally shadow, use shade to your advantage, avoid casting a large shadow.
If you can obey the four "S's" then you will be able to avoid detection by the vast majority of human beings. Maybe I should add a fifth "S" for "Stay Still" but you can move as long as it is slow and deliberate, keeping substantial vegetation between you and your target.
And remember, hide with pride.