I downloaded itch through google on my safari browser. Once you download it, you should see files in your hotbar or in the downloads button (which is on all web browsers like safari, opera, Firefox etc). Double click the file for itch and log in, from there you should be able to find this very page and download the Mac application. The same process will happen with the browser download button and all of that but this time you click the file that's named "mac". Once you double click to open you can play the game. {Theres probably grammatical errors left and right so I apologize}