Help i hardbricked my s3

Sorry if i posted this in the wrong Forum or if it was answered already (im new here )

I just rooted and i flashed the wrong custom recovery causing a hard brick on my s3. Odin mode , download mode, charging, powering on , DONT WORK

I just need to get this thing in download mode and ill be Good

EDIT:I found a solution (i think) http://forum.xda-developers.com/show....php?t=2369125

But i dont have a linux is it possible to do this on a mac since the terminal of mac and linux are very alike. If so, can someone rephrase the steps using a mac instead of linux.