Instructions
Travel to any Poke Mart, the building with the blue roof in each city. Buy at least 100 Max Repels.
Travel to the route that contains the type of shiny Pokemon you wish to catch. The shiny Pokemon you find in a given location is determined by the type of regular Pokemon you can catch there.
Locate a large patch of tall grass and stand in it.
Use a Max Repel from your item bag to stop any random battles.
Use the Poke Radar to make four patches of grass shake.
Stand in one of the patches of grass to fight a random Pokemon. Defeat or capture it. After the battle is over, four more patches of grass shake again.
Step into another patch of shaking grass that moved the same way as the previous one. For example, if your patch of grass shook for one second, step into another patch that shook for one second to fight the same Pokemon. This technique is called chaining; the more Pokemon you fight successively, the higher your chances of finding a shiny Pokemon.
Reset the Poke Radar if none of the patches of grass shake like the one you previously fought. To reset the Poke Radar, take 50 steps and use it again. Continue to use Max Repels to stop all random Pokemon from fighting you, as they will break your chain.
Chain 40 of the same Pokemon together to receive the maximum chaining bonus, increasing your chance to find a shiny Pokemon.
Use the Poke Radar continously after 40 Pokemon have been chained. Eventually, one of the patches of grass sparkle instead of shake.
Stand in the sparkling grass patch to fight and capture a shiny Pokemon.