When you download the upgrade you should see a EBOOT.PBP file inside it. Drag or extract the file to the desktop of your computer. Then connect your psp trough a 5 pin USB to the computer an open the file in "My Computer" and open the file. Next open the "PSP" folder and open "Games". Then create a new folder called "RECOVERY" and put or paste all the files inside. Next on the psp while pressing the "R" button and a pink menu will open. Next press the button which says "Run psp recovery file F:\PSP\GAME\RECOVERY\EBOOT.PBP.

How to enable flash player without WI-FI or Wireless LAN

When turning on the psp press "R" and a pink menu will opn. Next open "Registery Hacks" and click "Enable flash player".