If you are using git and github to maintain your code here are some quick and short commands to remember.

Create a new repository on the command line

Enter these commands one after the other using your command line tool.

touch README.md
git init
git add README.md
git commit -m "first commit"
git remote add origin https://github.com/username/project-name.git
git push -u origin master

Push an existing repository from the command line

This will push or in other words upload you local files to your remote repo.

git remote add origin https://github.com/manidf/javascript-enlightenment.git
git push -u origin master