In order to sync your local project on your computer to GitLab you will need to install and setup a Git client such as SourceTree.
Alternately, if you prefer using Git via the command line, you can find helpful documentation here: https://gitlab.blinkm.io/help/gitlab-basics/start-using-git.md
SSH Keys
As part of your Git client setup process you should create an SSH key.
Detailed instructions on how to do this can be found here: https://gitlab.blinkm.io/help/ssh/README
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Testing your setup
You can test your setup by running the appropriate commands on the command line, or by adding a new remote GitLab repository path to your local Git client and testing the pull, push and commit functionality.