Step 1. If you're not already on firmware 3.11, you update to 3.11. Simply download the 3.11 EBOOT, and copy it to your UPDATE directory under GAME, under the PSP parent folder. If you need to create one, be reminded that it has to be spelled in all capital letters.

Step 2. Download the rest of the files, namely the firmware 1.50 EBOOT and the downgrader archive released by Fanjita and Noobz. Extract these files into their respective folders on your PC first. It'll be useful to be organized like that.

Step 3. Browse through the folder contents of the extracted HEN/Downgrader files. You'd immediately spot the MS_ROOT folder, aside from the checkworks and SRC folders. Navigate to this folder.

Step 4. Copy the PSP folder inside MS_ROOT into the root directory of your readied memory stick. That's the topmost item in the file storage hierarchy for your memory stick (if you're using any file browser reminiscent to Windows Explorer's collapsible navigation list). Now this is important: you'll be asked if you want to overwrite. It's a-okay to give it a go, because custom data not related to the downgrader won't be overwritten.

Step 5. Follow this if you've downgraded to clear up your IDStorage. Execute the ID Storage Restorer in the Game Menu of the XMB. This should polish the IDStorage to wax finish. Once completed, you are now free to update to any official firmware.

Step 6. Back to basics. Check the extracted file for the PSP 1.50 firmware EBOOT. It's named EBOOT.PBP, so you'd have to rename it to UPDATE.PBP if you haven't already.

Step 7. Like Step 4, you'll have to copy the renamed file to the UPDATE folder under GAME, under the PSP parent folder. It's important that you do not execute the EBOOT immediately. You'll get a "Game Could Not Be Started" error, and no pretty, pretty lights for you.

Step 8. Get that UMD of Lumines handy, because you'll be loading it now. Instead of starting normally, you'll get to see pretty lights now. There won't be any messages, so you'll have to decipher the color code this way: red screen for "Try again," blue screen for "Time to downgrade."

Step 9. When you finally get the blue screen, you can execute X.YZ update under the Game Menu in the XMB. You'll have to navigate to it via the memory stick menu.

Step 9.5. On a side note (side, meaning this isn't really a mandatory step), you can also check if HEN is strutting its stuff while you're D-Padding your way around the XMB. Find the HEN version by checking the System Info under System Settings in the Settings menu. It should read 3.11.

Step 10. First-time downgraders will find that the downgrader will ask you to patch the TA-082 motherboard (assuming your PSP packs it). The button X is the way to go. You'll get a reminder of sorts, warning that the downgrader could break your PSP. Easier done than said (yes, in that order), apparently. If you couldn't care much about a bricking probability of less than 1%, then accept via the X button.

Step 11. The process completes with a notification that your settings are corrupted. You can restart your PSP (X is your friend), or run NETCONFIG restore to clear the muck up. With that out of the way, voila! You're done.