I searched the memory banks for times I tried to make others feel shame -- wish fervently they could go back in time -- and I came up with two main things.
One: times that people have said something homophobic around me. My responses have ranged from, "Could you please modify your language?" (to a couple of guys behind me on the bus) to, "You know being gay isn't bad, right?" or--if it's the second time or more--"You know I don't like that" (to people, younger than me, that I know fairly well).* My goal is immediate and, at least in my mind, clear: I want them to stop, and I want feeling bad to be part of what makes them stop. I am using shame as a pressure point, or maybe as a tourniquet. This seems all right to me: I don't have time to have a slow and reasoned conversation with them, because I need to stem the flow of aggression and spite. I hope, too, that next time they're tempted, they'll remember that they got grief for it last time and think, "Maybe it isn't worth it." Not a change of heart, but a change of surface.
Two: times that someone has asked me for something I do not want to give. Instead of just saying, "I don't want to do that," I try to make the person feel bad for asking me in the first place. This works in exactly the same way. It works as a tourniquet. Next time, maybe they won't tell me what they want. Not a change of heart, but a change of surface.
*I know these don't sound all that harsh or weapon-like. One reason for this is that I am not very brave. The other, related reason is that Option 2 for responding to shame--trying to find reasons why it was really okay to do whatever it was, and thus no shame is necessary--is a particularly common, and aggressive, response to this kind of assholery.