Yes, discipline is crucial. The AIC principal-- Ass in Chair--followed daily--or at least three times per week-- will pretty much guarantee you grow as a writer.
But how you approach your writing is just as important.
I often find myself counseling writing students on their schedules. Make writing a priority in your life. Writing comes before Home Depot, reality television shows, Facebook, jobs and dinner parties. Schedule it, and you plan your loyalty.
Easier said than done, I know. But here comes the Zen part.
You sit down to write without expectations. You may find a goal helpful--two hours or 500 words-- but in the end it's your attitude that will open the portal, and welcome the flow.
That means reserving judgement and editing for revision, not drafting.
That means your work can--and often will-- surprise you.
You just walk the path.
I can't say it better than Richard Bausch, in his interview, which I have photocopied and posted near my desk:
When I sit down to write, I'm not thinking about pulling stuff out of myself. I'm thinking about going somewhere, walking around, and seeing what I find. And there's never a time when I sit down and it isn't there. You just walk the path . . . I never worry about whether or not it's good. I don't care, right then. I'm walking the path. I know that if I can bring enough attention to it, and be honest and open to it and not cheat it, it'll be fine. I love William Stafford's advice. Someone asked, 'What do you do about writer's block?' Stafford said, 'Lower my standards and keep on going.' --Richard Bausch, Interviewed in Writer