I have a long tight dress with slits on both sides, its royal blue and black. What color heels I should wear?

Skirts and dresses with slits are very “in style” now. Black shoes would look chic with your long dress but you can also wear silver or gold with your dress. If you are planning to wear your dress for a special event in the evening, gold or silver shoes might be an option. Black color shoes are classic and will look good day or evening.