well,in this topic, i do have a powerful spell,but it's all about concentration.take any object that is of your liking which could be carried anywhere.
1. With your first and middle fingers trace a pentogram over the object.
2. Visualize electric blue or purple flames coming from your fingers.
3. Chant as you trace the pentogram "with this pentogram i do lay protection heare both night and day and to the one who should not touch let their fingers burn and twitch i know envoke thee: so mote it be"
if this is done properly it's quite effective.you can use it in case you get in real trouble.^_^