What would be the best way/program to jailbreak an iPhone 4S running iOS 6.1.3?

I have looked around and done things like this before, but not with an iPhone 4S, running iOS 6.1.3, A5 chip.

On iOS 6.1.3, it is NOT possible to jailbreak a 4s due to its A5 chip (only iPod Touch 4g, iPhone 4, and iPhone 3gs can be jailbroken on that firmware). Your best bet is ios 7.0-7.0.4, as Evasi0n7 has that covered.
http://evasi0n.com/

Hope this helped you out! There are currently no other ways. But if this helped, be sure to check out MY youtube channel!