When I have my laptop bag with me out in a public place like a restaurant, I put one leg through the shoulder strap and put it by my feet. I drew a picture of my technique for you. I am in a French restaurant in the picture. I am dining alone. I made my bag pink so you could see it better. No one can take your bag when it's in this arrangement, nor can you forget it. I'm about to eat soup in the picture.
