When you start to write, know that what you are writing is shit. It is supposed to be. It's a first draft, and it's OK. Anything can be fixed, but right now, get that ink on paper.
1. Read, and write notes in the margins. It's your book. Break it. Mark every time there is conflict. 2. Understand that writing is re-writing 3. You will learn more from cutting than writing. 4. Actively critique other writers work (like at scribophile.com) 5. Join a writers group...either online or IRL. 6. Bare your soul.
Websites to consider: 750words.com (write everyday) stackedit.io (simple mark up that can push to gist/github for revisioning) Google+ Saturday Scenes. (Read daily works in progress) www.narrativebreakdown.com podcast (writing craft podcast) deadrobotssociety.com (writing podcast) www.typehammer.com podcast (3 geeks writing podcast)
There is so much more, but what I really hope you take away from this is that you write Every Fucking Day :)