The phrase "to add color to an outfit" means to include or incorporate vibrant or colorful elements into one's clothing or accessories in order to make the overall look more lively or interesting. Full definition
That's the best and easiest way to add colors to your outfit without going awkward with the matching. (thefashionfolks.com)
In addition, you can also use these necklaces for adding some color to your outfits and you will always be able to make a statement with them regardless of how you wear it. (thefashionablehousewife.com)
So add the colors to your outfits in chilly months with this red leather jacket. (inkprofy.com)