A reminder: This post courtesy of Julie Jarnagin’s 101 Blog Post Ideas for Writers.
22. List the biggest mistakes you made in your first manuscript
For the purpose of this post, I am going to use Nowhere to Hide, my zombie apocalypse novel, because it is the only (non-fan-fiction) manuscript I’ve ever finished (minus the editing part, which is happening now). So, without further ado:
– I didn’t plan anything. While I’ve mentioned before that I’m not the planning type and that I tend to prefer just writing, I suspect that having a general layout (at the very least) would have significantly decreased the length of time it took me to finish this story.
– I wrote a prologue. I personally don’t see this as a ‘mistake’, exactly, but after having a number of people on Critique Circle tell me that the prologue was pointless and detracted from the story, I guess it was maybe a mistake. 
– I started a “shout-out” naming convention, giving my characters last names of famous horror-guru authors/directors/etc, and then promptly forgot about following through with it once I hit the fourth character.
– Looking back at certain sections of the story, I see that I rushed through things that I didn’t find as interesting, but are actually fairly important parts of the overall narrative.
– I didn’t establish character stories. I’m sure this isn’t a necessity for everyone, but if there’s one aspect of the planning process that I, personally, should be doing, it’s creating character backgrounds ahead of time. I tend to just go with the flow, and more often than not I find myself writing my main character’s feelings or actions to reflect how I think I would feel or act, but that’s not really a smart way of doing things. Not all of my characters can have my exact personal thoughts and beliefs. That’s just foolish. What I really need to start doing is establishing my character’s lives and personalities before I presume to write about them.
I’m sure there’s more, but I don’t really have to bash myself all night long, do I? 🙂
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I made many, many mistakes on my first manuscript too. The main thing I saw was it was imbalanced. One moment would have high-comedy, and the next would be dark and bleak. If done right, it can work, but it wasn’t done right. That’s one of the great things about writing, is critiquing yourself and growing.
It’s funny actually…I find that when I first write something, I’m in some kind of zone in which I feel like I’m so awesome and my writing is impeccable…then after a little while I start to feel like its all utter crap…and then a while after that I look back at it and start fixing some things and think, “Gee, maybe it’s not so bad after all”. lol Hopefully every time I go through these stages I’ll get a little better and a little better until I’m actually half decent. XD