Hold L + Y and press Right(2), Left, Up(3), Down, Left at the main menu.

At the main menu, hold L and Y, and press Right x2, Left, Up x3, Down and Left. No sound will make, but go into Create Player and you will have all the kits.

After entering Rule the Street from the main menu, go to your headquarters and go to My Squad. Then, while holding up and the left trigger, press Y,X,X,Y,B,B and then a keyboard will appear. Type in the player's name and then he will appear. Then just swap him with a player of your choice.

Up + Left + Down + Down + Right + Down + Up + Left
Right + Right + Up + Down + Down + Left + Right + Left

At the main menu,hold both the R and L triggers and press Y,X,X,B,Y,Up,Down,Right,Left. If you did it correctly, unlimited gamebreakers will be written across the screen.