After delivering Steven the letter from the president of Devon corp visit the president and talk to him to receive the Exp share.
you cant
No, only the Exp Share
yes, there is
Yes.
Except maybe for a cheat, the only way is to get an experience share from ruby, emerald, or sapphire (Fire red and Leaf Green works to if you have gotten to the point of the game at helping the guy with the PC) and put it on a Pokemon then trade it into your emerald and the you'll have 2. *note: you'll lose your experience share in the other game you traded it from.
deliver the letter to steven in dewford and collect it from the president
Get second place in the lottery
only by cheat codes
You give the red scale from the shiny gyarados to mr Pokemon
Pokemon ruby's version IS Pokemon ruby.
no unless you trade from ruby or sapphire.
You make your Pokemon hold it and it gets experience without battling (if in party) OR it gets double experience in a battle.