Id open the door and have a knife and say if your gonna try to hurt me dont think it wont come without a price and then ask with a big toothy grin "So anyways you wanted something?"
What do I actually do, or what do I not do but say online that I do to try and falsely impress people?
What I actually do is ask who it is and perhaps look through the peephole. Then I'll answer it if it isn't some cheesy "charity" or bumbling salesman (or *shudders* a Christian missionary). Most of the time, it is one of those people, because I don't have any friends and I'm a hermit who doesn't like to go anywhere or do anything.
If it's the latter, however, you are asking for, right now I can't give you an example of what I don't do, because my creativity doesn't just happen on command, it has to decide for itself when it comes out of its shell.
I tend to lock all my animals up so they can't run out, then look through the little peep hole thing, if they look official I don't answer because I don't like signing things for my parents...If it's my pizza then I open it as quickly as possible...if it's a boyscout or girl scout, i ignore them...and if it's just a random ol' joe...i'll open the door slightly and listen to whatever they say...Then usually tell them my parents aren't home and make a up a bs time for when they'll be back.