How to download and setup janus
Open terminal and run command
                                            git clone https://github.com/motiv-labs/janus.git
                                        
                                        git clone is used to create a copy or clone of janus repositories.
                                        You pass git clone a repository URL. it supports a few different network protocols and corresponding URL formats.
Also you may download zip file with janus https://github.com/motiv-labs/janus/archive/master.zip
Or simply clone janus with SSH
                                            [email protected]:motiv-labs/janus.git