I have Mac and iPhone too, you need to download the app on your phone first and create the account there, then goto telegram and download to your Mac with the Mac version and then when you goto sign in on your comp you will already have an account made on your phone, it should just ask you for your phone number, then at that point you can click on the link in the blog post and it will ask you to join the channel the scanner is on. Hope that helps, good luck.