4th Gen [HG/SS] Tips for Shiny Hunting?

So I'm currently trying to soft-reset for a shiny Cyndaquil in SoulSilver, and this is the first time I've tried something like this. I'm hoping you guys could give me some pointers. :)

I've never done it before, but doesn't it take a long long time?

Don't just check Cyndaquil but all three starters, the chance is big that you might find the other two shining instead; this is essentially three hunts in one so the odds are higher.

But there are no tips, just to look very well before soft-resetting. Good luck!