A, B, C's of Black Magic

If you are preforming a revenge spell, what is the best object to use that belongs to the person being hexed? Hair? Blood? Clothing? Teeth? Dirt from their home? Part of their vehicle?

I personally believe that anything that holds their energy can be used. It can be as simple as you said-dirt from their home. Whatever is accessible is usable. The important thing to remember is to tread carefully on how you obtain the object to link to the person. Like you said "part of their vehicle" to get that you would have to probably mess with their property and it's important in general not to do anything that puts you at risk legally (trespassing is something to be careful of too). Sure there are "ideal" objects for certain workings like if you are getting revenge on an ex-lover semen/their underwear would fit in nicely if you are trying to jinx their sex life/future romantic endeavours, but obviously that is not something you may have access to xP. So basically work with what you got and remember in workings knowing a person's name and birth date and having a photo of them can help a lot with focusing your work. Also channelling your raw emotion (sorrow/anger) I believe can be incredibly powerful when doing a revenge working.