Take an iron nail - rusty and old. On a dark night - moonless and cloudy, set upon
a smallish flat stone. With an iron hammer strike it thrice. At each stroke say:
Clavus Ferreus
Malleus Ferreus
Ferrum Refilum
Ferrum Nobilis
Score the stone three times across with the nail's point, then take the stone and
bury it far from the house. Carry the nail with you always as a charm.