That doesn't stop me from freaking out.
It goes a little like this: "I am so not happy with that sequence of events. It needs to be drawn out, and I need to really make it hurt more. And that one character—her backstory is WAY too complicated. I need to simplify while keeping her resulting personality relatively the same. And the dynamic between those characters needs more spark. Oh, and I need way more backstory for him! There are so many details I need to add to make these people real. The setting kind of sucks, too. I really need to ground this novel somewhere, because setting can really bring a novel to life. And speaking of "really," I probably have too many in the manuscript. The prose is so rough. Ack."
The first edit is a lot like the first draft. There is so much to do! It can be just as overwhelming to have a finished book that needs to be ripped apart and put back together again.
So what do you do? There's lots of ways to tackle that first edit. But I personally set just a few focuses for myself. If I look at everything at once, it's hard to tell what's most important. So I take a step back, and I think about 1) What is good already, 2) What is kind of crappy, 3) What is missing.
Then I try to figure out how I can make the good stuff great, the crappy stuff better, and what I should add to make the novel more like I envisioned.
I'll use Sidekick as an example.
1) Good Stuff
Plot is in decent shape. Needs filling out near the end, to draw out tension a little more
Characters pop. At least most of them, focus on adding more dimension to Colin and Trina, more history between characters could give more weight to current story
2) Crappy Stuff
That one scene near the end. That fight needs to be bigger, MC needs to get more defensive and upset.
Summarizing. Add Real Scenes for the important stuff that's summarized, and cut the boring summaries.
3) Missing Stuff
Setting is pathetic, needs more detail on every level. And pick a real place, lazy.
Backstory. Characters have known each other a long time. Needs to feel that way.
Details. Details. Details.
Those points may look small, but you all know they can mean pretty intense, sweeping edits. Once you have your own list, it's time to pick the ones you really want to focus on. Right now, I am working on all the Good Stuff and Crappy Stuff, save the prose. The Missing Stuff has taken a bit of a back seat. Sure, I add Missing Stuff at my whims, but I'm not looking for it.
You just can't do it all at once. That's okay! Sure, it's work. And it takes a long time. But splitting up the tasks helps me stay focused and prevents me from totally panicking. Step by step, the work gets done.
Good luck to all those working on their First Edit! I'm right there with you, and I have cookies.