Three decades of change -- email, computer security, surveillance cameras, normal people not giving a shit if someone's said to be gay -- have made huge swaths of these tips obsolete. The rest range from goofy (swiping your target's hat and replacing it with successively smaller facsimiles; pretending to be the target and challenging someone to a fight over CB radio) to unrealistic (first intercept your target's mailed application for a new car registration...) to overly niche (Work in a machine shop? Miscalibrate your victim's tools!). For all I know, some might be effective. But the writing is dull, and unless you have an obsessive need for revenge, reading H. Allen Smith's classic "The Compleat Practical Joker" will be a much better use of your time.