You would use the game shard or the action replay depending on which version you have
just type in the cheat list DG489HD4
you can't
There is no code to specifically beat the elite four, but there are some codes that makes it easier. As most of them specialize in one type in particular, they usually have a common weakness amongst their Pokemon.
First get a gameshark then look online for codes after that put the gameshark in the leafgreen game then type in codes. Also the codes can get you Pokemon and items instead of looking and looking you can get them easily. Most gamesharks are $15 to $20. Hope this helps ;)
You can't enter codes on Pokemon vortex bro... They're all scams.
You need to buy an action replay, then type in codes that you can find on the Internet
Go to Cheats -> Cheat list... -> Gameshark... and then type in the code.
type what you want into Google - like a cheat for Pokemon ruby games
I don't know the codes but go to Google and type what you want on what game and it should tell you.
You must first have a cheat device for example Action Replay, then you can put the codes on that
You can get the code on google and type in Pokemon Emerald ation replay cheat codes.
on the action replay before you start game