I don't recommend to new users doing this, especially with Wug's Toolkit for Nexus devices available for free. And I can't recall, but isn't Odin windows only? I think you have to use Hiemdall for flashing Android roms of a Mac. (Which I have read is a real pos program. Never used it though. Odin and mobile Odin are just so easy.)
Plus, using Fastboot and Terminal to input code can be daunting for those that didnt grow up with DOS. You can get by with Mac, it's just more frustrating to do so. And last time I checked, programs like winzip are free on windows, but cost money on Mac. I shouldn't have to pay money just to unzip or zip a tar or tgz file.
Windows is just easier to deal with on a day basis with Android, imo.
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I'm sure there are plenty of people, including myself, that can guide you along. Once you get the basics down, flashing roms, restoring backups, rooting and unlocking bootloaders is really pretty simple. And I can tell you from experience, it is almost impossible to brick an Android device. You can soft brick one, but restoring and rooting again takes just a few minutes. Which is why people are always flashing roms.