1.) First you'll have to open Cydia and ensure it has your SHSH blob for iOS 5.1.1 save, if not, your only hope is to upgrade to the latest 5.X SHSH it (Cydia) lists at the top of its home page (keep note of it). If no 5.X firmware is listed, you're out of luck; skip to step 11.)
2.) Backup your device using Package Backup from Cydia; this is the safefest way to get all your settings back while avoiding issues in the future (restoring from iTunes backup is well know to cause problems)
3.) Download the latest versions of both [URL="http://ih8sn0w.com/"]Sn0wbreeze[/URL] and [URL="http://thefirmwareumbrella.blogspot.ca/"]TinyUmbrella[/URL]
4.) Ensure iTunes is closed then connect your device to your computer, open up TinyUmbrella, select your device under its "Connected Devices" tree menu, click the "Advanced" tab and ensure "Request SHSH From Cydia" is checked. Keeping note of the "Save SHSH Directory", click the "Save SHSH" button
5.) Open Sn0breeze, use it to download the iOS firmware corresponding to the latest 5.X you kept a note of from step 1.). Once the download is complete, use it (in iFaith mode) to create a Signed CFW of the latest 5.X SHSH blob you saw in Cydia
6.) After the CFW has been created, follow Sn0breeze's instructions to get your device into Pwned DFU mode.
7.) Open up iTunes and it should detect your device in recovery mode; hold down the "Shift"/"Option" key then click the "Restore" button, browse for your SIGNED custom firmware and let iTunes upgrade and jailbreak your iPhone.
8.) When the process is complete, set up your iPhone as a NEW device, if you don't use cracked apps, skip to step 10.) otherwise proceed to step 9.)
9.) Open cydia, add the following repo and install AppSync from it (the official Hackulous repo is dead, incase you didn't know):
repo.ipastore.me
10.)
Sync all your desired apps from iTunes to your iPhone, reinstall
PkgBackup from Cydia and use it to restore your repos, tweaks and app/tweak settings
11.) Done
