I still have a 3.02 oeb-need help

You should be fine to upgrade to 3.52M33, then 3.52M33-4, then to a more recent custom firmware if you wish.

Format your PSP's memory stick from the PSP menu (all the way left, down to system settings, down to 'format memory stick'. I'm assuming you have a memory stick 256MB or bigger, and not a dodgy (probably fake) one from ebay. Dont forget to back up anything you don't have on PC first.
Download 3.52 M33 (release)
Download official sony firmware 3.52
Download official sony firmware 1.50
Follow the instructions in the readme.en from the 3.25M33 (release) download exactly to install custom firmware 3.52 M33.
You will need to either choose to open it with notepad, or rename the file to readme.en.txt then double click it.
Confirm it has installed ok. All the way left in psp menu, down to System settings, down to system information, check the system software version.
Download Custom firmware 3.52 M33-4 update
Copy the 'PSP' and 'seplugins' folders to the root of your memory stick. Root means not inside any folder, so X:\ (where x is the drive letter of the PSP), click 'yes to all' if asked to 'confirm folder replace'.
Run the 3.52-M33-4 updater from the game/memory stick section of the PSP menu.