Downgrade from lollipop to kitkat

[jaithehulk]

Hello everyone,

I have a Samsung S3( i kno its old but still love it ) rooted and running on temasek CM12.
I would like to downgrade it to SlimRom kitkat 4.4.2, is it possible?
If yes, what are the steps to do it?

Thanks,
Jaithehulk