[XY] Shiny Hunt Advice?

[HazelCapulus]

So, I've only ever gotten shinies from horde encounters in Omega Ruby, but after literally three days trying to get a damn numel, I've decided to skip over to X/Y and try my hand at poke-radar chaining. I have thirty or so max repels, a level one hundred pokemon to help me cleave through the wild pokemon I encounter, and a few hours free. Is there anything I'm missing? Are there any secret special techniques from the pros?

I know how the basic concept works: Don't interrupt the chain, keep stocked on repels, chain level forty is maximum chance, and so on. But I dunno if there's any finesse required, or if it's  just a matter of not messing up.