Need Lots of help! 3.90 Downgrade

Ok, heres the story. I haven't owned a PSP in the longest time and last thing i did was use DarkAlex's custom firmware, i think it was like around 3.3.

Well i got this new White PSP with the starwars logo crap on the back from my little bro and now i wanna downgrade this thing with that custom firmware again. I've been trying to read around but i dont understand a lot of this, it seems so much has changed i have no idea what "pandora's battery" is and a "magic memory stick" all im trying to figure out is how to get this thing down from 3.90to possibly 1.50 so i can get the 3.90 Custom.

Any help will be really appriciated!

Is this white Star Wars PSP a fat or a slim ?

Either way, you'll need a Pandora Battery and a Magic Memory stick to downgrade your PSP. You can get this by
1. Downloading some files, and getting someone you know with a PSP already on a CFW to modify a battery and memory stick using those, so they then become a PB & a MMS
2. Make the MMS yourself using some files, and then hard-mod a battery pulling a pin or something or other.
3. Make the MMS yourself using some files and then buy a pre-made Pandora Battery which goes by the name of a Datel Tool Battery.

Once again, it's 2AM so I can't be arsed finding any links for you, but there's literally guides everywhere.

Yea it is the Star wars psp, I dont know what the difference is between a fat or a slim one.

And where do i get the MMS Files? And Battery Tutorial?

Thanks A Lot for the reply btw.

So you've definitely got/know someone with a PSP on custom firmware to make them ?

If so - here's the tutorial I used to make my Pandora Battery & Magic Memory Stick (links to the files included), make sure to follow it carefully.

Btw, to tell if your PSP is a fat or slim look at this image. It's vital you know what type your PSP is, because the steps to create a Pandora differ for each.

You should really go to Dax's page,download all of the latest stuff and read all of the readme's.I have hardmodded my psp slim batteries to make them pandora,not recommended unless you have a steady hand.

Thanks for the help you guys, but i decided to do it all on my own, i figured it will help me out in the long run if i have any problems.

BTW, i got it to work
Downgraded from 3.90 OFM
to 3.80 M33
then up to 3.90 M33-3

Turns out Pandora's Batt is pretty easy to make
and the Magic Mem Stick as well.

And yea it is deff a slim psp.

Good news. :)