Repository maintainers can set contributing guidelines to help collaborators make meaningful, useful contributions to a project.
Setting guidelines for repository contributors
To help your project contributors do good work, you can add a file with contribution guidelines to your project repository's root folder. Then, whenever someone opens a pull request or creates an issue, they will see a link to that file.
Adding a license to a repository
You can include an open source license in your repository to make it easier for other people to contribute.