Ask a Mason "What do Masons do?" and you will likely see them stammer as they try to offer up a digestible answer. "It's kind of hard to explain," is probably the best response you will get on the spot. There are a few reasons for this.
For one, Masons as a whole don't all do one specific thing. Some will do volunteer work. Some will raise money for charity. Some will do social events. Some will do educational events. To a degree all of these things are part of Masonry if a particular lodge wants them to be, and yet none of them define what Masonry is.
You see, Masonry isn't about what we do. It's about what Masons are. Our reason for existing, which admittedly might sound like a corny answer in a casual conversation, is to take good men and make them better. What Masons actually do is help give other Masons the tools and support they need to go on an introspective journey. The tools of an operative mason help us understand allegorically how to smooth our own rough corners. The reason it's hard to explain is because you can't really see this journey. However, in time, you can see the results.
The question then isn't really what do Masons do? It's who will you become?