To help contribute and improve the TurtleCoin project, you can:
submit pull requests, or create issues over at our GitHub Repo.
help improve this wiki by submitting a pull request/making an issue over at its GitHub Repo.
help make various tools which need to be refined/be worked on (wallets, daemons etc.).
Check the GitHub Repo for more information.
The #bounties channel in the Discord has a list of bounties (pinned) offered to users who can help improve functionality in existing tools/make a tool which can be used.