This test repository is created for the members to test and learn to upload files to the github repository.
Navigate to the repository page
Press the "Fork" button in the upper right corner.
Now the copy of the repository will appear in your personal repository list.
More at https://help.github.com/articles/fork-a-repo/
Type
git clone https://github.com/<yourusername>/test_assignment
# enter the newly downloaded directory
cd test_assignment
# create a directory with your username
mkdir yourusername
cd yourusername
# now you can create a file there
echo "test" > test.txt
# add it to the control version system
git add test.txt
# commit changes
git commit -a
# this will require you to type the description, let's say "test" and save the file.
#push changes back to your personal repository
git push origin master
On your repository page, find "New pull request" button.
More at https://help.github.com/articles/creating-a-pull-request/