This stuff is pretty simple and straight forward. After working at Pacsun when I was like 17 I noticed this girl who used to come in and steal our clothing all the time. She was black and always pulled the race card whenever she was caught so we just quit bothering with stopping her. She never once set off our alarm. We knew she stole because each one of us had witnessed her doing so. Removing the sensor, price tags and stuffing the item into her over sized purse or handbag, what have you.
ANYWAYS, all you do is take your first finger and middle finger and bend the edges of the "rectangle" down with one hand as you pull the pin away with you're second hand. I don't condone this but I thought it was kind of neat to share.
They have made changes to some tags but the ones I still see around here work very well. Shown below as tan.
Pressure point > |------pIn-------| < Pressure point
Pressure Points: Bend both points upward away from pin and it will cause the sensor to release the pin and detach. Congrats... You have successfully stolen some sort of article of clothing.