If you want to help make XMPP and the programs using it better, here are some infos and links that might help:

You could help the XSF by working on the Extensions:

It’s really important to improve the clients too, only if the clients support the cool XEPs you can make full use of them and this is where I see the best potential to help. For example there is not a good iOS client (in my opinion).
So if you are good in or want to learn:

  • Python - contribute to Gajim or poezio
  • iOS development - contribute to Monal
  • Android development - contribute to Conversations
  • C++/Qt - contribute to PSI or swift
  • C - contribute to profanity

Other ways are spreading information about XMPP and help people to use it. Writing articles and so on. To ask for help from the Pros join: