Connect your iDevice (iPhone 4s or iPad 2) to your computer and backup all data.
This is essential when you upgrade your iPad 2 from iOS 4.X version to iOS 5. If you perform Upgrade and not restore on the iPad from 4.X version the jailbreak will not work. You need to perform Restore then do the jailbreak and after that to restore from backup.
Close iTunes and start Absinthe.
Press jailbreak button and wait until instructions tell you to open jailbreak app on your springboard.
Normally this app will jailbreak your iDevice, but for now Chronic-dev servers are overloaded so there is a trick to continiue and finish the jailbreak process.
Without doing anything else aside, open settings and set VPN to ON, error will pop up, wait a little more without touching anything else, the iDevice will reboot and after the reboot it will be jailbroken :)