Fork The Repo; When you login into your github account, you should see your repositories on the right-hand side of the screen.Fork the repository by click on the Fork tab at the top of the page this means you are making a repo means making a copy of the project on your GitHub
Clone The Repository by typing git clone- <link to the repo> in your terminal. Cloning means creating a local directory in your computer that you can work on.
Fetch the repository by typing git remote add upstream <repo link> this ensures that you get updates every time the master repository is updated.
Now you will have two remotes
1)Origin- That is the one you forked and you can make changeto.
2)Upstream- Is the original repository
Pull the repository by typing git pull upstream master For you to make changes in the original repository
Pushing the changes; you create a branch(A section of the changes you made) by typing git checkout -b my-changes on your terminal
Push your branch to the repo you forked by typing git push -u origin my-changes
Send a pull request by click the pull button on left side of the screen.This will let other know about the changes you have made.
You can explain the changes you have made in the comment section.