When choosing your colors for your event, take into consideration of your centerpieces, any draping done on the walls, and chair colors.
When choosing which colors go where, you want it to be balanced, but yet not look super busy as well. If you have centerpieces that have a lot to them, choose a simple table runner(for rectangle tables) or overlay(for round tables), and chair covers that match your table linen with a chair tie to match your napkins or runner.
If your centerpiece is simple, choose a vibrant runner or overlay that stands out from your table linen, and choose a chair cover that matches the table runner. So for example, if you have a black tablecloth, with a gold centerpiece, choose either a white or ivory runner and white or ivory chair covers with a black chair tie. Your napkins should also be white, ivory, or gold.