As easy as 1, 2, 3...
Somewhere along the way I learned that three items will make an outfit. A blouse and skirt won't do it, but a blouse + skirt + JACKET or a blouse + skirt + VEST or a blouse + skirt + STATEMENT BELT... you get the idea. So if in life three is a crowd, then in fashion three is key.
This occurred to me as I tried to work a beautiful silk embroidered Chinese jacket with a pair of coral skinny jeans. The pants picked up some of the embroidery on the jacket, so it worked without being too matchy-matchy. I had the au courant black velvet bedroom slippers lined up. It didn't look thoughtful enough until I threw on a double strand of plastic buttons that I bought for 25 cents at a garage sale eons ago. From a distance those buttons look like a rainbow of beautiful bakelite beads. Up close they are, of course, buttons, but the hues and shape transforms them into jewelry. That "third thing" made the outfit.
Try it sometime. When you've got two things you love, but they aren't singing well together, add a third something. Remember that if the third is an accessory it needs to carry the tune as well.