Here is a guide on how to get iOS 6.0 Beta 1 on any iDevice that supports the firmware without a developer account or using your UDID.
Supported iDevices:
iPod Touch 4th Gen, iPhone 3GS, iPhone 4, iPhone 4s, iPad 2 Wifi/GSM/CDMA, iPad 3 Wifi/GSM.
Step 1: Download the latest iOS 5.1.1 for your iDevice from here (place it on your desktop for easy access).
Step 2: Install iTunes 10.6.3 links below
iTunes 10.6.3 Windows 64x Download
iTunes 10.6.3 Windows 32x Download
iTunes 10.6.3 Mac Download
Step 3: Download iOS 6.0 Beta 1 for your corresponding iDevice Here (place it on your desktop for easy access).
Step 4: After downloading the 2 firmwares and iTunes 10.6.3, open iTunes 10.6.3 and connect your iDevice via USB. Backup up your iDevice to iTunes (Disclaimer: everything iDevice will not be held responsible if anything goes wrong in this process).
Step 5: After backing up your iDevice… windows users hold shift and click Restore Mac users hold option and click Restore and select your corresponding 5.1.1 firmware and proceed to Restore.
NOTE: This is essential, after restore completes on iTunes setup your iDevice as a NEWdevice (NOT YOUR BACKUP!). Also on your iDevice go through the setup process, to proceed to “Start Using iDevice”.
Step 6: With a fresh iDevice running 5.1.1 with it’s factory settings (iDevice still connected to iTunes via USB) windows users hold Shift and click Check For Updates Mac users hold option and click Check For Updates and select your corresponding iOS 6 Beta 1 Firmware. Proceed to update to iOS 6
Step 7: With your iDevice still connected to iTunes, right click on it’s name in the left side navigation bar and select “Restore From Backup…”
Done! Enjoy iOS 6.0 Beta 1