The project has build instructions for building your own copy. These are terminal commands.
You may need to install additional software if you get "command not found" errors. If you Google the exact error messages + the name of your distro, you should find out how to install that. The instructions seem comprehensive, though.
Mint is based on Ubuntu, so the Ubuntu steps should work. I'm not sure what version of Ubuntu the latest version of Mint is based on, though. You can probably find that info somewhere on the Mint website.