first thing you need is a Pandoras batteryhttp://www.dealextreme.com/details.dx/sku.12472

then you need to have a magic memory stick for this you will need a memory stick then downlaod the file from here
http://www.digital-kaos.co.uk/forums/downloads/psp/20/rains-ultralite-mms-maker-4-01-512/
put it into the root of your memory stick.

after press the L trigger insert the Pandoras battery and then insert the magic memory stick and wait about 10 seconds press x and it will turn off dont worry turn it back on go to system information and it will tell you what firmware you have

Ok i just have to say that you need to edit a little first of all you can also make your own pandora this is an good video for making your own (note this is for the slim only!) um and also with the mms you don't insert it in to your psp you plug your psp in and it makes it for you thats all i have to say

Nice guide!