Touch of red
When the clouds have taken over and it is dark and gray and I feel like going back to bed instead of jumping into work, I found that the touch of red can help lift the mood. It's red because it's my favorite color so in this case, a touch of color can act like an alarm clock for the internal system being a red or burgundy lipstick, a pair of red shoes, a blue or green scarf, a pink coat or knit or anything that might work for you and help put a smile up instead of dreading the day ahead.
I am all for a great monochrome look but when I add to it a red lip I feel like I can take on whatever the day is throwing at me. I also find that a pair of red shoes can change an outfit and make it stand out, and the same goes for a red scarf agains an all black look or an earth tone coat.