Showing that you help doesn’t mean being a publicity hog. Bragging about your charity work is akin to congressman or mayor putting up a billboard announcing his “accomplishments.” It is extremely tacky and does a little to endear you to anyone but the most gullible. What will set you apart from the others who also volunteer their time and effort will be the effect that you have.
Anyone can be convinced to give money or spend painting school rooms, but few will have enough skill and talent to pull of a large project with long term positive impact. Remember that the goal is not a quick fix but a strategic intervention with long lasting effect. Good deeds have a way of coming back and any help to society as a whole generally leads to positive over-all effects. Keep in mind that in helping others, you also help yourself.