I suggest that you not try that method for you have a 1 in 999 chance in getting a shiny. The best way to get a shiny is to use a pokerader and carry lots of max repels and ultra balls, or quick balls.
The pokerader increases the chances of finding a shiny in half. All it takes is a lot of luck and patience. Either that or you can cheat with cheat codes, but be careful with those becuase it might screw up your game or game console. good luck and hoped that helped