In a Mars hour of a Mars day (Tuesday at dawn) make a pentacle to Mars with the following symbols, one on each side:
Make the pentacle out of clean paper in red ink, or engraved in iron or steel.
When it is made, light a white candle, and some mars incense (dragon’s blood for example, or cinnamon or pepper if you can stand it), and then say the following out loud:
"Source of all that manifests through symbolic Word into this loving World, hear me and grant that the mighty spirits Madimiel, Gheuriel, Ithiel, and Barchethiel administer through this pentacle the distribution of the forces of Mars that being armed therewith, if I am attacked by any one, I will neither be injured nor wounded when I fight with them, and their own weapons shall turn against them, as it has been written:
Their sword shall enter into their own heart, and their bow shall be broken.
Their sword shall enter into their own heart, and their bow shall be broken.
Their sword shall enter into their own heart, and their bow shall be broken.
Their sword shall enter into their own heart, and their bow shall be broken.
Their sword shall enter into their own heart, and their bow shall be broken.
"Thou spirits Madimiel, Gheuriel, Ithiel, and Barchethiel, hear me and turn all weapons and attacks sent against me back upon those who would see evil done upon me. Let every spell and scourge of God sent against me be returned to their source. May all evils aimed at me be returned upon them. Accept this offering of fire, and of smoke, and go forth to do these things for me in power."
Walk away.
Revisit it on Tuesdays, at dawn, and say the last bit again. Include those you want to protect in that bit if you're doing it for others.
The end.