WordShell is a bash script. Therefore, you simply copy it onto your machine and make it executable (run the command: chmod +x wordshell). To make it easily reachable, put it in one of your system’s standard system folders (e.g. cp wordshell /usr/local/sbin/).
Then, you can check that you have the other helper programs that are needed or helpful by running “wordshell –checkrequirements”. You should then install anything that was missing. If you intend to work on remote FTP / SFTP / FTPS sites then lftp is not essential, but will make life a LOT faster (http://lftp.yar.ru), especially the first time you synchronise a site.