I messed up rooting need help

[AsapAvi]

When I was rooting my samsung galaxy device I followed all the instructions carefully and everything went right. When the phone turned on it was really slow and all these error messages came up like
"unfortunately, the process.android.media has stopped", "unfortunately, TouchWiz Home has stopped" ect. I would like to know how to unroot my phone and make everything how it was before. PLEASE I need to figure this out by today. :'(

 

[GSDer]

The first thing we need to know is what model/carrier your phone is.
Then, if you can post a link to the steps you followed to root.

Probably the safest way to return to stock would be to use the Kies software on your PC. It'll prompt you for the model number and IMEI (both listed under the battery) and it'll take care of selecting the correct firmware for your phone.
If your phone is (somewhat) working you may even be able to use Kies to backup your information before reloading the firmware.

Sent from my rooted, debloated, deodexed Sinclair ZX-80 running CM -0.001 using Tapatalk 2

 

[AsapAvi]

Fido and it's I747M
Root Galaxy S3 I747M 4.1.1 - YouTube This is the root I did
I did a factory reset and it works but the supersu is still there I don't know if it will do the same thing later on should I still do the kies thing ?