Heads up: NOTHING will work if you don't believe in it. Also, start on easy seeming items. I started out with inflicting pain on myself with a pain spell to become stronger before i practiced other things.
I don't usually teach, but this is one of the first spells I did. (warning: with this spell, you might lose your voice for a little bit, depending how strong you are/ how much hatred you put into it.)
If you want to have a easy revenge spell for beginners you will need:
1 tablespoon pepper (chopped up)
enough water to fill the jar (not to the rim)
any size jar
small pice of paper
hatred for the victim
Put the pepper in the jar and pour in the water. Close and shake the jar and wait for the water to turn brown (This process wont take long, but wait about 10 minutes or more to have a darker brown.) Then, write down the FULL name of your victim and imagine some of the stuff they have done to you. Imagine their face as you put the paper into the jar. Close it and shake again. Then take a lit candle at an angle and drip wax onto the jar lid until you finish chanting this. It acts like the negative energy's seal (No, it does not matter how much wax ends up on the lid, but try to spread it out)
"You have done wrong to me/to a friend
you must suffer like I/a friend did
why you decided to do what you did is beyond me
so mote it be"
(Heads up: during the time you are holding the candle at the angle, the flame may become enlarged. This is not bad at all, but rather showing that it is working)