Everyone has an angle, a rule, a strategy to get themselves to write well.  Get the advice from writers who have made it work for them.  

1.    "You've got a good character when you know what he would say at any moment or to any question or any situation that arises." -Stuart Beattie
    
2.    "A lot of the time, it's more interesting what the characters are not saying than what they are saying."  -Alex Kurtzman & Roberto Orci   

3.    "Every time you're in a scene, you've got to know, 'What's the point? Why am I doing this scene?  What am I saying?' As soon as you say it, get the hell out. That's it."  -Peter Tolan

4.    "All you have is your voice and your unique take on the world. If you can follow that and forget about everything else, that's where you'll achieve success." -John Hamburg

5.    "The most valuable thing I did as a writer was to take an acting class.  And once you understand what the actors are looking for, that's how you write." -Paul Attanasio

6.     "Everybody wants to say cool dialogue. That's all there is to it." -Sheldon Turner

7.     "When I'm writing, I think, 'I want an actor to read this and say, "I have to be the person who gets to say this out loud." -Callie Khouri

8.     "I think discipline is the most important muscle for a writer. You do have to get into a certain rhythm, writing-wise, to convince yourself to do it every day." -Simon Kinberg

9.     "I think that the most important thing is to write something that you passionately believe in that you see really specifically. Be true to that." -Nick Kazan

10.     "I think what marks bad dialogue against good dialogue is the absence of subtext. You have to have it." -Billy Ray

11.     "I think working creatively around other people working creatively creates its own energy." -Jim Uhls

12.     "I spy; I talk to people. I will watch a lady at Rite-Aid. I'll tend to listen to her and how she speaks and I'll emulate it." -Nia Vardalos

13.     "I keep a huge amount of notes and notebooks, and of characters I see or things I hear or ideas or dreams or whatever. I collect those things." -Jose Rivera

14.     "I keep asking myself, 'What's the worst thing that could happen to this character?'"  -Paul Haggis

15.     "It's so important to give yourself permission to fail when you're trying anything creative." -Susannah Grant

16.     "Part of the craft of screenwriting is to write in such a pithy way, it's almost a combination between a poet and a journalist." -Robin Swicord

17.     "The skill, to me, is knowing when to follow the outline, and when to not." -Ed Solomon

18.     "We feel like it's not enough to make people laugh, we want to make them feel something." -Peter and Bobby Farrelly

19.     "If you are not intending to write something that's never been written before, then you're wasting everybody's time." -David Seltzer

20.    "Writing drunk is so much fun. That's why you can't do it." -Scott Rosenberg

21.     "You've got all these weird rules in this parallel universe. It's fine to have weird rules; they just have to be consistent rules." -David Goyer

22.     "First and foremost, I think if you write a really compelling story everyone will want to be involved in that." -Ted Griffin

23.     "Jack [Klugman] gave us the key, and it's one sentence: 'What do I want?' And that's critical. That's all you need to know." -Babaloo Mandel & Lowell Ganz

24.    "Some writers are just not capable of [outlining] they just don't like it. I work the other way, maybe it's my legal training. There's no tried true way." -Jonathan Hensleigh

25.     "Words are the last things that people do. They have the thought, they have the fear, they have another thought, they want to run, and finally, they speak." -Marshall Herskovitz

26.     "You have to have the one screenplay that will change your life. It may never get made, but good material gets known in Hollywood." -Bruce Joel Rubin

27.     "I try not to have anything that is rigid or structured or restraining, because you never know where the scene will take you if you allow yourself to go there." -Jeff Nathanson