Some quick briefing about what happened. I did flashed my S3 and managed to get cyanogenmod (custom rom 4.3.1) and the cellphone has been so damn buggy and I hate it so much that I would like to get it back to default android.
After some research on forums such as androidzone,x-da developers and so many other forums.
All I ask, is for a guide which I can restore my phone to factory settings.
Thanks alot guys!