Then how should i do it?
The OP forgot to tell you.
You have to press the keyboard buttons 'N-U-D-E-A-N-D-H-A-W-T'.
Your .iso must be the V:2.0 revision.
You have to have V.1.0 of Brawl to use the cheat. Nintendo removed it in V.1.0. Search 'Super Smash Bros Brawl Version 1.0' on Google...