Banish Spell

Get four small pieces of paper and on each piece write the person's name or the name of whatever it is you need to banish. On the opposite side draw a pentacle. Write the same name on the pentacle and carve it on the black candle.

Do what you would normally do as far as visualizing this thing or person being drawn away from you. At this time ask any deities or personal patrons for help if you'd like.

Light the candle. Take the four pieces of paper and burn one, saying,
"I banish ______ with the power of fire. So mote it be."

Bury one in some dirt, saying,
"I banish ______ with the power of Earth. So mote it be."

Flush one down the toilet, saying,
"I banish ______ with the power of Water. So mote it be."

Then tear one into little pieces and throw it out your window, saying,
"I banish ______ with the power of Wind. So mote it be."

Let your black candle burn down.

If you prefer to work outside, you can obviously use a stream instead of your toilet. It really doesn't matter how you do this, but it is important that your intention be clear.
Also it is important to be careful anytime you are working with fire or burning things.