So you want to contribute to some open source project which is hosted on git[hub,lab] or some other git website. Here is all you want to do.
Fork the repository
Create a personal fork. On github, visit the project repository and hit fork. It will fork the project in your personal account.
Clone it in your local machine so you can work on it. Remember you are cloning the fork, and not the original project.
$ git clone firstname.lastname@example.org:USERNAME/project
Add the upstream
Add the original project as upstream.
$ git remote add upstream https://github.com/ORIGINAL_PROJECT_USERNAME/ORIGINAL_PROJECT_REPO
Fetch latest work
If you forked a project just now, you can go to next step. If there is a time gap, fetch latest work from upstream to your fork.
$ git pull upstream
Create a new branch
Create a new branch so you can work there.
$ git checkout -b develop
Add your contribution
Add your work in new created branch. Commit changes. Make sure to write meaninigful commits.
Push your work live
Push the changes you have made to remote origin.
$ git push
Create a pull request
Go to your fork page and create a pull request. That’s it