How to Get People to Fall for Pranks

Pee-yew!

Car Pranks are some of the easiest pranks to play on someone. I take my lead on these from your everyday weddings ceremonies. Use the bar of soap to cover the front windshield. Just rub it on and it will cover the glass like shoe polish. It even looks almost the same. Your victim will think it is just shoe polish and try to use the windshield washer and wipers to remove it. This causes the soap to foam up and takes forever to get completely off of the glass. But hey, at least they will have a clean windshield.
If you can open the hood of the car, drop a few cloves of garlic onto the exhaust manifold (output) of the engine. The driver will be well on the road before the garlic gets hot enough to start stinking and coming in through the vents and windows. A full bulb worth of cloves works really well.

Just don't chew it!

Household pranks are some of the best to pull. Wait till the kids go to school. Take a sleeve of paper cups into their room along with a pitcher of water. Place the cups on the floor as close to each other as you can. Use the pitcher to fill the cups to the VERY top. This makes for a hard time removing the cups (one at a time) and encourages them to clean their room as well.
Before the floor is covered however, remove the covers from their bed. Use the tin foil to cover the entire mattress. Place the fitted sheet over the foil and remake the bed as close as you can to how it originally was. Once they are done with the cleanup of the cups they will think the game is over, yet come bed time they get one more very loud, cold, and unexpected surprise!

Mmmm. Tasty!

Dormitories are the most notorious place for pranks. There really is no room off limits, and the RA! This is a multi-part description, so stick with me.
As most dorm room entrances have 1)doors that open inward and 2)tile floors or foyers, this works great. Make sure your target is in their room. Fill the trash can about 1/3 of the way full of water. Carry it to the victims door and lean the can against it to where the weight of the water and can are mainly on the door. This should leave the water level close to the top edge of the can. Knock on the door and run!
If your target is away and leaves the door unlocked, sneak in and remove the curtain rods from the window. Slip 10 to 15 small pieces of the shrimp cocktail into the rod, replace the curtains and hang them back over the window. If he has his own toilet just lift the seat and cover the lid tightly with cling wrap. Make sure there are no wrinkles in it. Now, go back out of the room and close the door. Slowly pour a large glass of water under the door, being careful not to get the hall carpet wet. Next, dump the laundry detergent (the more the better) in front of the door and use the hair dryer to blow it under the door. It will mix with the water and turn into a hard, dry cake. This is the prank that pranks for days. Trust me.

Office pranks are my favorite. Just make sure that your target has a good sense of humor before delivery and execution. This is, after all, your source of income.
While your victim is away wrap 2 rubber bands around 2 pencils. Twist the pencils until the rubber bands are tight and ready to spring. Place a handful of the plastic insects in the pen/pencil drawer of the desk. Push the drawer until there is just enough room to slip the two pencils in. Ease them in where the top of the desk is holding them against the bottom of the drawer and ease it the rest of the way shut. Sit back and wait for the pencils to scatter the toys and cause a little fright.
About a week after the first tiny (and somewhat weak) prank, place a paper cup half-full of vinegar in the back of their desk file drawer as far back and in the corner as you can. This creates a slowly increasing stench that will linger long after the vinegar has dried. While you are at it go ahead and turn their chair over, drop in a few pieces of shrimp cocktail and a wad of paper. Most office chairs have a single hollow cylinder that will accommodate this act. They will move all of their belongings (yes, even their chair) to try and get away from the smell. This could go on for months.
Finally, the office Coup de Gras, in my opinion. Wait until your co-worker (not your boss) goes into his office and shuts the door. Sneak up to the door quietly and place sheets of cling wrap over the door in a wrinkle-free fashion. Then go back to your desk and call him on the phone. Tell him you need his help right away. Then watch as he dashes out of the office and...