Answer:
There are a few ways:
1) You have to have the mental capability to completely reject it, and you need to find the item or person it has attached itself to and cleanse it. Immediately cleanse and bless the house, and DO NOT do this alone because the spirit will most likely attack a lone person. This will only push the succubus out and make it so it cannot come back.
2) You can completely destroy and kill it. This also takes a great deal of mental strength as you must rip it asunder and mentally light it ablaze. Again, stressing this fact, it takes a GREAT amount of mental strength and experience to do this. Beginners can get hurt doing this.