Flatten out empty packet
Fold in half lengthways (across long side)
Fold in half again
Pull down right side at middle of packet at right angle
Fold right section back under left
Fold left under right
Tuck the end you just folded under into the pocket created
Fold the top section down into the pocket creating a square.
Fold the square inwards into the pocket to create a perfect triangle
Now you have a neat and tidy crisp (chip) bag - no more scrunching them up and taking unnecessary space in the rubbish (trash).