The most important thing that needs to be mentioned before we begin is that this is not a spell to bring harm to the person you need to protect yourself from, it is simply to keep them away from you. It is important that you have the intention that this spell be mutually beneficial. To do otherwise is not in accordance with the Wiccan Rede.
Your regular altar tools (for circle casting, elements, etc.)
Four Thieves Vinegar (Usually apple cider/white vinegar as base with garlic, and sometimes with herbs such as rosemary and sage. Many recipes can be found online)
1 Black Candle
Parchment Paper and Pen
Ideally, this spell should be done during a waning moon, but emergency circumstances may not allow you to wait. If you must, this spell may be done during any moon phase. However, if you can, it is best to wait for a waning moon.
Cast the magick circle. On the parchment paper, write the name of the individual whom you need protection from and set it on the altar. Pour the four thieves vinegar into the cauldron. Place the black candle on top of the paper and light it. Visualize the person as clearly as you can as you watch the candle burn. Say, “In the name of the Goddess and the God, I seek protection from _____. May he/she be prevented from causing me harm. Let this be for the highest good of all, harming none.” With the black candle, light the parchment on fire and allow the ashes to fall into the cauldron, mixing with the four thieves vinegar. Hold the black candle over the cauldron and allow several drops of wax to drip into the mixture. Then snuff out the candle and break it in half, symbolizing your separation from the person. Close the circle.
The next day, dispose of the four thieves vinegar mixture. This should be done outside, but not too close to your house. (I was lucky enough to live on a 10 acre wooded property, so this was not difficult for me). If you don’t have a large property, simply do this as best you can. You could even let it run down your driveway, as long as it flows away from you. You want to keep this person and their energy away from you.
Finally, dispose of the 2 black candle pieces in two separate locations, far from one another. Again, this symbolizes the separation between yourself and the other person, as well as their inability to get to you and harm you.