I am a newbie as well, but I found the following works really well for me (please note that I use a PC so I'm not sure if this works well on a Mac):
1. I get the course up and running in my browser (i.e. access the command line as an Administrator (type cmd and then press ctrl-shift-enter); change the directories until I am in the directory containing my course; type "grunt build" and then "grunt server")
2. I then open GIT CMD (which I had previously installed), go to the correct directory and then type "grunt dev". After it has done its thing, you will see the word "Watching..." at the bottom. This is good.
3. I then edit my json and other files in Brackets, type ctrl-S to save the changes as I go, and then refresh my browser to see the changes.
I'm not sure if this is the cleanest way to work, so I welcome any comments from Oliver or others, but it works well for me. I hope this helps!