you will need a dollar bill and a toilet paper roll
Step 2: Setting it up
ok now get a toilet paper roll that is currently being used roll some paper off the roll but make sure it doesn't break now put the dollar bill in the roll and roll it back up and act like nothing happened after u r done.
Step 3: The funny part
just wait till someone goes #2 in the bathroom that u set the prank up in and you will hear a "OMG!!!" or "what the!!!" hope u liked it!!!