Charity: How to Convince Someone?

I don't think you can. Unless your life has been touched in some way by a death, disease or disater, most people wouldnt have that compassion and giving spirit for charities.
Just from things Ive experienced in my life, I'm more partial and have found charities I've never known existed.
Maybe find something they have a soft spot for (kids, homesless, etc) and take them to a charity event and let them see why the charity is in place first hand and who it helps.

After I go through the "they could do this and they should do that". I eventually get to the point where I look at my self to see if I am doing all I could or should be doing. Not just in regards to the situation that might be troubling me, but in other ways too, so that I can improve upon them and become a better example. I believe if anyone is to be convinced, this approach is more apt to do it.

I don't think you can convince someone to give to charity. It has to be a personal choice. Most people give to charities that mean something to them. I give to the American Diabetes Association because my grandmother is dying of diabetes. You have to be compelled to give not convinced to give.

it is voluntary act, to convince is a difficult thing, so as a first step you will have to establish your genuiness, give proof of your programs etc, you should be a registered organisation with the government. Once you collect donation from somebody noble, please make it a point to give feedback to the same person as to how his money was utilized, give an account, ask for his opinions if he thinks there are better ways of utilization, like that you may get good referrals to increase the base of your donors. Also seek tax concessions from authorities for people who donate you.