Step 1: Download Evasi0n v1.3 [Windows, Mac or Linux]
Step 2: Download iOS 6.1.1 for iPhone 4S. Update your device to 6.1.1 via iTunes. DO NOT update via OTA as it might cause issues with jailbreak.
Step 3: Since instructions to jailbreak iOS 6.1.1 with Evasi0n are exactly same as before, check out our detailed guide on how to jailbreak iOS 6.1 here for iOS 6.1.1, which assumes no prior knowledge.
Source: http://www.redmondpie.com/jailbreak-ios-6.1.1-untethered-with-evasi0n-v1.3/
