How do I upgrade my SCH-S968C (Straight Talk) to at least version 4.4.4?

[AC Question]

So I've recently purchased a Galaxy S3 SCH-S968C, from Wal-Mart and I'm having so many issues on figuring out how to upgrade to version 4.4.4. I have little to no experience in this field what so ever, that's why I'm here. I've heard of people being able to download Kitkat without the need of rooting their phone, however I haven't had any luck with anything. Any help would be very much appreciated. Thanks! P.S. Been trying to figure this out for 5 hours now...

 

[VW Maverick]

Welcome.
Found this: http://forums.androidcentral.com/ask-question/474126-why-won-t-my-samsung-galaxy-s3-update-os.html

Mav.