It is shirk ("shirk al-akbar") to believe in superstitions like astrology, horoscope, fortune-telling, amulet, talisman, lucky and unlucky number, animal, object, or else, because everything happens by the will of Allah.
It is shirk ("shirk al-akbar ") to give Allah any of the names and attributes of creation. For example, it is shirk ("shirk al-akbar") to assume that the essence of creation is the essence of Allah.