...for the person behind you.
Listen, we need folks to use proper manners. Follow the five step rule. This means if someone is walking behind you they are five steps away from getting to the door, be polite and hold the door for them. Do this instead of letting it slam their face.
Now on the flip side. If someone holds the door for you, be sure to say "Thank you". And of course the proper response for that is simply "You're welcome".