1. Revising. There aren't any shortcuts. I revise quite a bit before my agent and editors take a peek, and then revise more after they give me their comments. I don't think anyone writes the Golden Draft...maybe I'll produce a copper or bronze one someday. :)
2. Waiting. Once I send work to my agent, he sends it out on submission...and I wait. Sometimes the wait isn't all that long, but sometimes it's months. I try to deal with it by writing more. And if there's a deal, then there's another wait on the contract (which is where your agent truly earns his money and is worth every penny of his commission). Sometimes that wait is only a month or so, but I've also had to wait close to a year because of problems with boilerplate contracts, and my agent had to take on Viking Death Ships full of lawyers. (Luckily, he ate his spinach.) And after the contract is finished and you sign it, there's another wait for the money to arrive—anywhere from a couple of weeks to three months, depending on where it's coming from. If there isn't a deal, well then...
3. Rejection. It still happens. Getting published once isn't a golden ticket to getting published again, and getting published in the U.S. doesn't mean other countries are going to hand over bags of money for translation rights. One market will look at my series and say "Gimme!" and another will look at it and say "Meh." The answer to rejection, like waiting, is to write more, because otherwise I might chew glass.
4. Fear of #3. Even though I now know beyond a shadow of a doubt that I'm capable of writing publishable books, I still look at my writing at times and conclude that it isn't good enough. "Whine," I say to my wife, "whine whine this sucks whine whine." She tells me to shut up, I do, and write more. It's the only thing that can possibly make the sucking stop, after all.
Right now I'm enjoying coffee with this seasonal creamer in it—it's called marshmallow mocha. Mmm. Hope you're taking advantage of the season's opportunities for warm, comfy drinks. And writing more.