Instructions
Insert a copy of "Pokemon: Fire Red" or "Pokemon: Leaf Green" into your Game Boy Advance system. Enlist the assistance of a friend who also has a Game Boy Advance system. Insert the "Pokemon: Sapphire" game into the second system.
Travel to the Safari Zone in "Pokemon: FireRed" or "Pokemon: LeafGreen." It is located north of Fuschia City. Move to the second section of the Safari Zone and explore. The Lucky Egg is a hold item sometimes found on Chansey or Blissey.
Attack Chansey or Blissey until it is weakened. Use a Safari Ball to capture it. Alternately, if you have a Pokemon with the "Thief" ability, use this ability to steal held items. Pokemon can't steal items if they are already holding one.
Save your game and turn it off. Connect your Game Boy Advance with your friend's using a Nintendo game link cable. Turn both systems on. Make both players travel to a nearby Pokemon Center. Go to the second floor of the Pokemon Center. Have both players speak to the Cable Club representative to bring up the trade screen.
Select "Chansey" or "Blissey" from your menu of Pokemon to trade to "Pokemon: Sapphire." If you stole the Lucky Egg from Chansey or Blissey, attach it to a Pokemon first and trade that Pokemon to "Pokemon: Sapphire." Press "Yes" when prompted to accept the trade. Save both games and turn the systems off.