On occasion you may wish to try out a sandbox or experimental project. A sandbox project is a module or theme that contains experimental code that is not yet ready for general use.
Sandbox projects are not packaged for download, so the usual way of getting them is by "checking them out" using Git, the software used for managing Drupal code.
If you haven't used Git before, the good news is that it should be relatively quick and painless.
- Install Git, see the handbook guide.
- From the sandbox project's page, click "Version control" tab and follow the (one step) instruction for "Setting up repository for the first time".
This will get you the project code, which you can then install on your site like any other module or theme.