By assuring the public that lawful concealed carry can and is being accomplished every day by many many good citizens, without incidence. Shall-issue concealed carry has been the law here in WA for many many years, and the safety record among citizens carrying is very very good. I'd speak to the psychology of carrying concealed, and assure people that I know those who carry weapons to take if very seriously and educate them that carrying a weapon actually makes people more risk-aware and risk-avoidant... and that it certainly does not make people trigger happy and eager to jump into an unnecessary conflict.
I'd assure people that the crime-deterrent effect of an armed populace is real. That even if they do not carry themselves, that the idea that some of the people walking out into a dark mall parking lot at night might be armed, has a deterrent effect on those who are looking for easy victims.
And I'd take as many of them shooting as I can. Especially those that are a little squeamish about guns simply because they've never been exposed to them. That's how I've been able to change more than just a few minds. But the public needs to know by our words, and by our example, that we are as serious about public safety as we are about our right to carry. And that's what I always try to get across on threads like this. It'd be nice if I didn't get a bunch of backchatter for it from people like you.
We agree on the information that needs to get out there. But, as you say, the logistics of doing so is what I was asking about. Every firearm owner trying to hit just one other person with the info isn't very effective. It also loses the "strength in numbers" effect that a lot of political protests use so effectively in influencing legislators. Talking over firearms with your co-worker is one thing, standing there with a bunch of other folks listening to an NRA Instructor expound on the virtues of a high ride holster vs a bellyband is something entirely else.
Another possibility would be a "Famous Faces" lecture tour that could make the rounds to various schools, civic groups, ect... Get local or National high profile people to do a circuit that would garner some positive publicity.
Another, if you still want the individual effort angle, would be for the various National gun groups to try and get a Nation wide "take a friend to the range" day. Try and emphasize the need to convert first timers into firearms safety and fun.