Not so long ago, a very wealthy Hindu lady came to see me. She sat down and told me, "I would like to share in your work." ... It occurred to me to say to her, "I would start with the saris. The next time you go buy one, instead of paying 800 rupies, buy one that costs five hundred. Then with the extra 300 rupies, buy saris for the poor."
Simplicity itself: give to the hungry some of your bread and to the naked some of your clothing.
For the most part, I am something of a tight-fisted cheeseparer, and the only time I buy clothes is when I go somewhere and forget to pack enough to wear, so the poor would notice little benefit if I gave them a 38% cut of my clothing budget.
On the giving to the hungry some of your bread angle, though, I recently thought of an even simpler idea, based on the custom of setting an extra plate at the dinner table for an unexpected guest: You divide your monthly food budget by the size of your family, then give that amount to a food shelter. In effect, you're spending enough money on food to feed one extra person the same stuff you're feeding yourself.
I haven't yet screwed up my courage to estimate my family's monthly food budget, so I mention this not to lecture anyone on the proper way of charitable giving, but just as a suggestion for whoever has the means and interest to give it a try.