The easiest way I have found to get shiny Pokemon is RNG reporter.
Sure, it's a lot of work to go through and get your SID, but once you have that... smooth sailing from there on out.
I've been lazy, but I've gotten a shiny Skarmory, Smeargle and Ralts through breeding. It's kinda fun.
This. So far with help from the RNG I've caught or hatched these shinies (in no particular order).
Mewtwo, Darkrai, Shaymin, Palkia, Ho-oh, Zapdos x2 , Suicune, Cresselia, Regigigas, Regice, Regirock, Registeel, Azelf, Uxie, Smeargle, Nincada, Phione, Skoropi, Yanma, Pichu, Gible, Igglybuff, Aerodactyl, Ralts, Togepi, Shroomish, Scyther, Combee, Rattata and Bidoof.
And I've found these random shinies over the years (in order of being caught).
Wurmple, Smeargle, Octillery, Wingull, Starly and Gastly.