There are many ways that one can contribute to Puppy. If you have started a project, you can always inform others about it by starting a new thread in the forums. You can even start a Wiki page for it! (Eg. 1∞; Eg. 2∞) You don't need blessing from anyone to start your own little project, though it would be beneficial to search and make sure that no one else has done what you want to do first. This helps avoid duplication and wasted efforts. If you want to start you own puplet, make sure you have read through Barry's FAQ∞.
Interested in writing some documentation for Puppy? Have you acheived something in puppy where you had to hunt down a whole lot of information from various sources? Chances are someone else will have to tread the same path unless you make up a how-to. You can start by editing this Wiki or join the documentation project.
Finally, you can always volunteer yourself to any of the existing project by sending pm/email to their initiator or maintainer (usually the person who has started the forum thread).