Requirements :
1)A phat/slim psp which has custom firmware 3.52m33-3 or any firmware above it.
*Minimum requirement is 3.52m33-3*

Guide

1) First of all,you need to set your kernel to 3.xx/4.xx.You can do so in recovery mode or in your VSH menu (if you have the VSH addon plugin installed)

**Recovery : Hold the off switch for 3-5 seconds,then HOLD R and boot your psp up.Now go to configuration,and click X at the "Game Folder Homebrew" option until it displays as 3.xx/4.xx kernel.Example : On a 3.52m33-3/4 psp,it should show as 3.52 kernel.

2) Download the 5.00M33 installer : http://exophase.com/files/psp/5.00M33.rar

3) Download the 5.00 eboot.pbp : http://exophase.com/files/psp/500.PBP

4) Use your preferred software to extract the 5.00M33 rar file.You should now get two folders (UPDATE and Translate) as well as a readme.txt file.

5) Copy the UPDATE folder and paste it in ms0:/PSP/GAME.
  
   ** It should now look like this : ms0:/PSP/GAME/UPDATE/eboot.pbp **

6)Time,for the 5.00 eboot (step 2).

7) Copy the 500.PBP and paste it in your ms0:/PSP/GAME/UPDATE directory.

   ** It should now look like this : ms0:/PSP/GAME/UPDATE/eboot.pbp and 500.pbp **

8) That's all,seriously.All you need to do now is to run the installer on your PSP.

  ** The installer will seem very official like,but don't worry,that's how it's supposed to be like **

9) Remember,once the update is over,PRESS X/O when it asks you to do so or your psp will brick!!

10) What else,enjoy!