Step 1: Find someone with a perfectly good scarf.
Step 2: Chase them down.
Step 3: Grab hold of the scarf and don’t let go.
Step 4: If you aren’t able to ruin it by yourself, enlist a friend.
Step 5: If necessary, tear at it with your fingers.
Step 6: Repeat steps 3 and 4.
Your scarf should now look like this: