A segula is protective or benevolent incantation or ritual in Kabbalistic and Talmudic tradition.
Wearing a red string
A sigil is a type of symbol used in magic. The term usually refers to a pictorial signature of a deity or spirit. In modern usage, especially in the context of chaos magic, a sigil refers to a symbolic representation of the practitioner's desired outcome.
Goetic seals from the Lesser Key of Solomon