Jailbreak iOS 5 5.0 on iPhone 4 iPod Touch iPad with Redsn0w
Step 1: Open Redsn0w and select “Extras”.
Step 2. Click “Select IPSW” and browse to where your iOS 5 firmware is.
Step 3. Go back and click “Jailbreak”.
Step 4. Follow the instructions on screen to put your device in DFU mode.
Step 5. Wait for Redsn0w to jailbreak your device and have it reboot into tethered mode.
Step 6. Click “Back” on Redsn0w, and then click “Extras”.
Step 7. Select the boot tethered option and follow the instructions to put your device in DFU mode again
Step 8. Wait for your device to reboot, and you’re done!

How to: Fix Cydia White Icon After iOS 5 Jailbreak Redsn0w
Step 1: Open up Redsn0w and navigate to extras.
Step 2: Make sure your iDevice is plugged into your computer and powered off.
Step 3: Click the “Just Boot” Option in Redsn0w
Step 4: Boot your device tethered

SemiTether – iOS 5 Untethered Jailbreak Simulator !
A new Cydia package called “SemiTether” jailbreak for iOS 5 is now available on BigBoss repository which basically helps reboot tethered-jailbroken iPhone, iPad and iPod touch without having to plug in your device into PC or Mac. This is second best thing to having an untethered jailbreak. The only one downside to it is that it doesn’t allow you to use Safari, Mail, Cydia, and jailbreak apps installed on your device.
Step 1: Once you are done with tether-jailbreak, Start Cydia, and add http://thebigboss.org/semitether as repository on Cydia.
Step 2: Now search for “SemiTether” package on Cydia and install it! You are done!

List of iTunes Versions

List of IPSW