training advice?

[infinty]

i need some help to raise my pokemon, what or where is the best way of training? is it true that if you battle only fast pokemon your pokemon will gain more speed?

[Near]

Elite Four runs I guess.

Yes, it IS true, and what truth it is - EVs [Effort Values] change your stats by quite much.
252, which is the max benefiting Evs, will add to your stat 63 points.

Have a read:
http://www.serebii.net/pokedex-rs/ev.shtml

[Fate37]

if u want your dream-team, ill teach you how to clone pokemon.to clone items, let the pokemon your cloning hold the item.clone rare candys!!!! here we go:

1. go to battle tower and have the pokemon you want to clone in your party.
2. go to the pc and deposit the pokemon you want to clone into an empty box.
3.save the game
4.withdraw the pokemon you want to clone
5.go to the link multi battle room. when she says "to continue, the game must be saved. is that okay", say yes. on "would you like to save the game",say no.
6.turn off the game

if you did it right, you should have one of the pokemon you cloned in your party and one in the emty box. you can clone up to 5 pokemon at a time.no matter what, it wont do any damge to your game. hope i helped!!!!!;)