You could contribute to any of the many free software projects that are trying to develop federated or P2P versions of common centralized services. Or, you can contribute to projects such as Freedombox or Freedombone which are trying to make running home servers easier. @bob runs the Freedombone project. Maybe, you can talk to him. Then, there are community mesh network projects such as the Commotion project. There is no end to the work that needs to be done to build a new better Internet. It really depends on what your specific interests are. I like programming. So, I mostly write and contribute to free software. But, there is a lot of advocacy and awareness work that needs to be done too.