I would suggest you start with the basics. You shouldn't even cast a spell before you have learned the basics and studied and practiced them.
Judging by your profile and picture, which you have none, I would think you are new to this whole thing and jump to the conclusion that you are only here for a spell to invade someone's privacy for selfish reasons. If I'm wrong you could tell us how long you have been studying magic, what you study, why you study that, and the like. If not then, you probably won't get far on here in terms of help.