You could always add a statement necklace, but chandelier earrings are a heat-friendly alternative (at least for those of us who get hot with a giant necklace/noose around their neck in warm weather). Bonus: bold earrings really pop with an updo or ponytail hairstyle, too.
Outfit details follow.
Tee: J. Crew Factory (exact)
Skirt: Athleta (similar)
Sandals: Steve Madden (similar)