Step 1: Fork the repo.
Step 2: Clone the repo.
Step 3: Head to the issues tab.
Step 4: Find an issue that interests you and matches your skill set.
Step 5: Have queries regarding the issue? Comment on that issue and you will be replied within a few hours.
Step 6: Now start working on the issue.
Step 7: Once completed, generate a pull request.
Step 8: If your work is accurate and significant it will be merged to the master.
You are also free to contribute your own idea or creation. And ths thing is enouraged even more.
Feel free to mail me at: [email protected] for any help or queries.
Happy Coding :)