###Fork the repo
Please pay attention don't directly push your dirty code into the main branch, Fork it first!
###Set remote upstream & origin
path-to-your-project-folder$ git init
`path-to-your-project-folder$ git remote add origin 'your own repo url'
`path-to-your-project-folder$ git remote add upstream 'the main repo url from the group/organization'
###Create Pull Request
Once you finished with new feature put your code into your own repo, then you could create a Pull Request to merge your new feature into main repo.