Comments
It looks like you are looking for advice on how to fundraise, particularly in a way that contributes to creating a norm or culture of giving.
Substantively, as a step one, trying to convince someone to donate all of their income above a certain threshold is likely to be met with a degree of defensiveness, internally, if not externally. If someone is not already considering such a step, it is probably very difficult to persuade the person to make that step. If you are a part of a community of relatively wealthy people, being a part of it and forming friendships with people might be a place to start. You can make it clear that giving effectively is part of your identity without explicitly trying to pitch them on effective giving, which may influence people. You could introduce people to Giving What We Can, and let them know the pledge that you have taken. However, being influential of other people in this way is likely very hard and would involve skills that are likely very difficult to learn.
On a meta-level, you might want to include in the title of your post the kind of help that you are looking for. "EA, I love you" tells people who might want to help you virtually nothing about the kind of help you are looking for.
Good luck persuading/influencing people to use the power they can to significantly better the world.
I think if there were proven methods to persuade such people to give away the excess, the world would look very different.
I hope you find success in persuading those around you to give, but I don't think the process of giving to neighbours and polling resources rather than going directly to supporting specific causes where they could have a lot of impact makes much sense.