Make a Boobie Trap

Ever wanted to get back at that certain person? Or just want to laugh at other people's expense? That's possible using fun, inventive booby traps!

Steps

Open your door and use some duct tape to tape some Heavy-Duty string onto the top-left or right of the wall, opposite to the door going to the sandal.
Place a sandal on top of the opened door.
Make sure the string is also going from the bottom left or right to the other side of the door.
Sit back and wait for someone to come through and watch the effect of your booby trap.

Decide where the enemy is most likely to go. For example, trails, clear areas, gates, etc.
Get any type of weapon that will not harm the target, but will deflect the target. Snappers, water balloons, party poppers, etc.
- If you want to use the party poppers, anchor one end to a stick or rock that is heavy (so it won't move) and at the other end tie the string on the popper with your trip wire. Anchor the popper to another end with nails, tape, or screws depending on where they are.
Tie the wire at one end to a steady object (rock,stick,etc:). The other end should be connected to a pin, the pin should have two loops. One connected to the ground and the other attached to a system of pulleys going to directly above the path. Tie the water balloon(s) to the end. When the pin is pulled the string will fall, and so will the water balloons.

Make sure your victim can take a joke like this and make sure they don't get hurt.
Have a hiding spot or tell the people that you are outside playing while you sit back and watch the fun.
Be sure it is safe. The trap should be tested in case of any harm.
Does not have to be a sandal as long as it's not harmful