Use your head.
I mean my god, is there something wrong with your head? Maybe the day that they were handing out common sense you were sick or maybe you just couldn't get to the store because you were too busy rocking away to whatever boy-band fills your boots these days?
But one things for sure, you ended up at the dumb-ass store, grabbed a trolley and grabbed all the stuff you could get didn't ya?
He ment take a picture with your camera or some form of picture capturing device.