Thanks for the input, you guys! Apparently I'm one of the few who are a bit abnormal and don't write chronologically.
My brain doesn't think that way until way after the fact.
So I start, well, I just start with what I see in my head. And only ONCE has it ever been what turned out to be the beginning. When I write, it's like building a big giant puzzle with, say, a thousand pieces where you don't know what the picture looks like. While I've got about 200 or so laid out and ready to assemble, I'm still missing the other 800 pieces, right? Somehow, they hopped out of the box and skittered off somewhere to bide their time. So I work with what I've got until I stumble across another handful of pieces. And then another and another.
All these pieces come to me in what's basically a jumbled mess. As I piece together a little scene here and another one there, I start to figure out where they all tie together. It may be just one tiny little sequence association, meaning I'll have to figure out the big chunk between two parts, but it's something right?
It's a start.
And that's what I've learned through what you guys have told me and my experiences. Whether to start with a totally sucky beginning and then go back to fix it later or just starting with what you think might be the beginning and going from there, we just need to do what works for us. And as much as I wish I could be one of those writers who tweet things like "one more chapter to go and I'll be done with this draft!" I'm realizing I just need to accept that that's not me as a writer.
So I'm off to do some drafting (after I finish this revision from hell that I can't seem to get through) ... and hopefully I'll know what this puzzle picture looks like sooner rather than later :)