Step 1: Stroll in McDonalds during busy hours or even if it's quiet and swipe a receipt or two from an uncleared table or from the top of the bin if it's super full and hope there are items on there that you like, the best way of making this not look suspicious to any employees is to carry a pen and jot down a few numbers on it as soon as you pick it up, it will also stop anyone watching thinking you're up to something.
Step 2: Make up an issue with the food, I like to say stuff like "The burger looked like Stevie Wonder had put it together then Mike Tyson had punched it a few times" but be careful if it's a local store you do not want to be memorable at all so you can rinse the method again and again, so simple things like it was missing pickles, or you only got 3/5 selects you paid for, or the fries weren't salted and were cold, use your imagination.
Step 3:
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Step 4:
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