1. Put a Pokémon that knows FLY in the first place in your lineup.
2. Put the "Golden Gyarados" in the 6th position.
3. Put the Pokémon whose colour is to be changed in the second position.
4. Put all Pokémon into your PC, except for the Pokémon in the 1st position.
5. Take out the Pokémon which you wish to change the colour of. It has to be the one that was in the 2nd position before it was deposited.
6. Go to the Bug Catching Contest on a day which it is held.
7. DO NOT ENTER THE CONTEST. Say NO the attendant, and enter the park.
8. FLY out of the contest, back to where you deposited your Pokémon.
9. Store the colour changing Pokémon in the PC.
10. Go back to the Bug Catching Contest, say YES and then complete the contest.
11. Now go back to where the Pokémon that is to become shiny is. Locate it in the PC and look at it.
12. It's Shiny!
13. It'll have the "Golden Gyarados"'s name, so you'll have to train it untill it evolves.
14. It is done. A Shiny Pokémon is yours!
Have a listen! Also, When you're in Mahogany town, and TR still have that Pokémon controlling machine working in the hideout, turn on the radio and tune it to the right hand side. You'll see "????????????" and hear some strange beeps and sounds!