Some authors hate it. Some authors love it. Most authors are probably somewhere in between. Rewrites. They're a necessary evil if you want to get your manuscript anywhere; we all know our first draft is not publishable. Neither is the second or even the third. Rewrites occur on several levels, and it can be hard to keep track of them. More importantly, it can be hard not to get lost in them. Some authors keep rewriting and rewriting without eventually publishing anything. This isn't wrong, but if publishing is your goal, you will have to stop at some point. You will have to trust your manuscript and yourself.
First of all, after you finished your first draft, it is advisable to put it aside. Some will say to do it a few days, others will say a few weeks or even a few months. Personally, I think this is up to you as a person, although I would suggest taking a few days, just to come down from the high you were riding while writing it. You'll see that when you do so, you approach your manuscript with more clarity.
So, how not to get lost?
You want to create a step-by-step plan that will work for you. The advice I give here is solely based on my experiences as a writer as well as what I would be looking out for as an editor in various editing stages. If you're going to self-publish, I suggest not yet announcing any publication dates at this point whatsoever. Some more seasoned authors might because they have a process that works for them, but unless your manuscript is rather clean from the start, I don't advice announcing anything at all. Keep it to yourself until you can be sure of things!
Read your manuscript without changing anything. Just sit down and read so that you can get that fresh perspective. But if you're anything like me and like to be busy, you may want to highlight things that aren't working. Different colours for different items such as plot, character development, grammar. Print it out, read it on an Ereader or your computer. The choice is yours.
Make a checklist of the following things: timeline, plot holes/inconsistencies, scenes that can be cut, and character development. When you have done that, read it again and mark if the timeline makes any sense, whether there are plot holes and inconsistencies you need to be aware of, if there are scenes that can be cut (kill your darlings), and if your characters go through any kind of development. Do they really do something or are they placeholders? Perhaps characters need to be cut or changed in order for them to fit. This is the moment you want to take notes.
Start your rewrites. Some people like to write a completely new draft; others prefer to rewrite bits and pieces. However you do it, keep the checklist at hand.
Send your rewritten version to a few trusted beta readers (only a handful) and ask all of them the same questions. Ask them if the story makes sense, if the characters make sense, and how they think you could improve the story. You could add more questions of course, but don't do too many. You don't want to overwhelm them or yourself. Feel free to ask about the positive aspects too, though. It can't be all that bad.
Rewrite according to your beta's feedback,
Rinse and repeat steps 4 and 5 until you are satisfied with the story. At some point, your rewrites will flow into self-editing, for which you can find tips here.