it means that trouble is coming this way. look it up in harry potter lyrics for double double toil and trouble, and you'll get your answer.
It was supposed to be a "spell" they were doing.
The play that contains these lines is Macbeth by William Shakespeare.
You could ask around on the guild Boards, they usually have a good layout maker on them. Just ask! Search around a request for a layout which has Boil Bubble Toil Trouble on it!
It means that trouble is coming.They sing this in Harry Potter #3
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