If you're not familiar with poppets or dolls, you can read up on Voodoo dolls before you keep going with this revenge spell:
Cut a rough person shape from two pieces of black fabric and sew them together with red string to make a poppet. Use more red thread to sew two Xs where the eyes would be. Stitch the pieces of the poppet firmly so the contents don't leak out between the stitches.
If you are using a drawing to represent someone, make it accurate with features that would distinguish them (proper hair color etc.) and write their full name on the image. Now rip up the picture into little pieces and stuff them all inside the poppet. Add a good dose of dirt dug from a graveyard (not necessarily a fresh grave, but dirt from within the boundaries of the cemetery) and some patchouli. Give it a little shake to mix the contents and finish sewing it up.
Now bend the two arms together and sew the "hands" to each other. Take the doll and bury it upside down behind your home.
Yes, sorry for the silly spell titles. I can't help myself sometimes. This one uses the reflective power of a mirror to return bad energy back to someone who deserves it. The results on your target will usually be closely related to what they did to you in the first place. A very appropriate Voodoo revenge spell.
Do this spell after the sun goes down, though you don't have to actually be in the dark when you perform it. Pour rum over the mirror, and leave it on a cloth or in a dish to air dry on its own. Once the rum has dried, use a brush to paint a thick X over the face of the mirror.
Repeat the name of the person you are casting the spell on 5 times, and then smash the mirror (do this over newspaper or cloth to minimize the mess). Gather up the shards and throw them in the garbage. Even though the mirror is not left intact, it's reflective energy persists to keep this Voodoo revenge spell active until it reaches your target.