The Magickal answer 
:
You can anoint a black candle with a protective oil such as thieves oil or another protection oil recipe. That will keep you protected during the course of your spell. After that, cast a banishing spell. If possible do it along with your friend or have her do it since the work is mainly for her.
The Wiccan answer 
:
- Make sure that you have exhausted every other possibility such as as sweetening spell.
- Divine twice and cast once.
- Aim to banish “all negativity from around you” first instead of targeting a specific person. Often times that is enough.