Things to keep in mind before doing a prank:

Make your number private or call using free web messengers so that you cannot be identifiedPlan out the story and your character well. Make sure that the person you are calling does not take it too personally.Write down the whole script and rehearse your dialogues, but it can not be guaranteed that everything goes according to the prank call script. If the person says something unexpected is impromptu in improvising.Disguise your voice and change your accent if you know the person who you are calling. Refrain from laughing when you are performing the prank. If the victim hears you laughing, the prank will fail.Understand that the prank must be funny and not harassing and offensive.Refrain from recording the conversation as this can be considered offensive. Have some fun!