If it wasn't for advice from others, my writing would suck a lot more than it does right now. I don't think there's a good writer alive who hasn't had amazing advice. So, let's share it.
Some amazing pieces of advice I've gotten:
1. Become the person you are writing the perspective from.
2. Cut the first scene of your manuscript.
3. Kill all cliches. All. Even on the prose level.
4. Read your manuscript out loud.
5. Don't expect revisions to be done in the time frame you want it to be. Multiply your 'ideal time frame' by five and that might be more realistic.
6. Get a diverse set of beta readers. Writers that read different genres, come from different backgrounds, different ages, etc. You need multiple perspectives on your book. Beta readers are the best thing to ever happen to your book other than, well, you writing the book.
7. Learn learn learn about your subject. Write what you know - and if you don't know it, get to know it. Here's a very old blog post I did on this subject. Might be the most important advice ever, in my opinion!
8. Do whatever it takes (as long as you don't end up in prison) to get your book's voice/mood correct. For me, that meant writing it in longhand first, then writing it on a Word doc that had black pages and white words.
YOUR TURN. Share your best writing advice, however obscure it may be!! What is some really good writing advice you've gotten, advice that you constantly keep in mind while writing?