In your repository, create new pull request
to merge fork to master repo (ie the original repo you forked)
GitHub checks whether your requested merge creates any coflicts.
If all is good, click on Create pull request
Write an informative message explaining your changes to the master repo administrators. Click on Create pull request
The repository owner will then review your PR and either merge it in or respond with some guidance if they spot a problem.
Check original repo to see your merged changes