When they are sleeping put a table over there head and make a loud noise which wakes them up causing them to smash there head on the table :)
you can put jello in his shoes
put a furry hair bobble next to your friend ,pretend to be asleep then wait to see how she reacts!!!!
I am not sure but my Friend told me that u could prank a friend on the prank patrol website
After pulling a prank on a friend, you should yell "Gotcha!" or "Prank war!" to convey the playful nature of the joke and signal that it’s all in good fun. This helps ensure your friend knows it's a lighthearted moment rather than something mean-spirited. Always be ready for their reaction, as they might want to retaliate!
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do something funny
pull a prank on him
you need to go to bbc.co.uk and for aussies: http://prankpatrol.abc.net.au/prank-a-friend/
You can view videos of the skirt pull prank and learn how to perform it from the videos at the YouTube website. Once on the website, type "Skirt pull prank" into the search field at the top of the page and press enter to bring up the information.
they drew on his face
fill it up with balloons and sour cream, or just balloons.
Peter put a dead mouse on Mr. Dussel's bed as a prank.