If you post about how to, you know, finish a piece of writing, or even just finish [an early] draft, I will REVERE you. I've been reading your blog long enough to know you have a hard time turning down reverence, i.e., just long enough to know how to manipulate you shamelessly.
A girl who properly uses "i.e." (as opposed to "e.g.") is a girl after my heart or, at the very least, my attention. So here we go....
We live in a society of exchange. And the way things operate (whether they should operate that way is irrelevant) has been burned into our psyche since birth. When you work, you receive something in return. Most of the time it's money. Some of the time it's food, drugs, or sex. (I mean, who hasn't received a blow job after doing some yard work?) Simply put, when we work, we expect to get paid in some way, shape, or form. If there's no tangible return, it can sap our motivation and we can lose our sense of purpose. Even if we don't want this to be so, this paradigm remains in our subconscious and we just can't shake it.
For part-time writers or aspiring writers or writers in between paid gigs, lofty ideas of writing for the sake of writing or for the sake of art or even for the love it just do not cut it on that subconscious level. You can intellectualize all you want about how writing is all about the process and not the outcome, but, if you don't anticipate some kind of reward when you finish a particular piece writing, it's going to be an uphill battle.
The reason that you, Moose in the Kitchen, are able to write and post blog entries on a regular basis is because you know that people will be reading them. You can see the tangible evidence on your hit counter or in your comments section.
When it comes to longer pieces of writing, in which we don't know if they're going to be published or produced, the promise of an audience disappears.
There are several solutions.
1.) Find a way for drafts of your work to be tied to some kind of deadline and payment, particularly around the time your rent or mortgage is due. When I receive new-play commissions, for example, they are usually broken down into installments. I get some money upfront, some more when I deliver a first draft, some more when I have subsequent drafts, and some more when I turn in a final draft.
2.) If you're not yet in a place where people will pay you for your work sight unseen, then hook yourself up with a writing workshop, whether you're writing plays, screenplays, fiction, or whatever. A community of like-minded individuals with similar interests and goals provides a support system that can motivate and inspire. And make sure that the workshop assigns firm deadlines.
I have a remarkable reputation in the playwriting workshops I facilitate in that just about every student (actually all of them in my last one) finishes a full-length play by the time the workshop is over. This is because they are required to bring a certain number of pages into class on specified days. They know that, if they don't, they will have wasted a significant chunk of class time in which somebody else could've brought stuff in.
3.) You don't have to sign up for something as formal as a writing workshop to have a good support system. There are plenty of informal writing groups in all genres that you can join, or you can start one yourself. But make sure your group assigns deadlines.
4.) You don't even have to meet physically for something like this to work. You can join or start an online writing group through Yahoo Groups or some similar service and trade your work and feedback over the Internet.
(A word of warning: The feedback sessions in writing workshops and groups can be damaging and not conducive to the writing process, especially when you are working on a first draft. First-draft feedback should be, above all else, encouraging. In my writing workshops, I have a rigid set of parameters about how to give feedback on first drafts, and perhaps I will post it someday soon.)
[Addendum: I did indeed write a post about giving feedback, "Most People Don't Know How to Give Feedback to Writers."]
5.) If you're writing by yourself without the support of a workshop or group or commissioning theater or film producer that hired you, then you are working in a vacuum, and most of the time self-imposed deadlines do not work. "I'm gonna finish this screenplay by October 1st" rarely results in a finished screenplay by October 1st.
I have a couple suggestions to get around this. If you're writing a play, do some research on some playwriting contests. If you're writing a screenplay, look into screenwriting contests. There are contests for every genre of writing. Find some good upcoming contests, and set yourself a deadline based on a contest you want to enter. It's pretty good motivation to get your writing done if you know you have to send it off by a particular date in order to win some money or some other cool prize.
6.) One more thing that I have done with plays (and you can do this with screenplays and other forms of writing as well) is to schedule a living room reading of the play long before it's finished. (Or set one up at a theater company if you have the means and connections.) That's right. Before the script is even close to being done, contact your actor and writer friends and tell them you need them to help you develop your script and to give you feedback. Pick a date. Believe me, there will be a fire under your ass when you know that ten people have cleared their schedule to be at your house to read your work. The least you can do (besides providing tasty food and cold beverages) is to finish your damn play. You know how embarrassing it would be if they showed up and you only had 20 minutes worth of script to show them or if you had to call everyone up at the last minute and cancel? It's the perfect way to dent your reputation, fall out people's good graces, and humiliate yourself.
All these suggestions point to tangible rewards for your work. That said, don't fall into the trap of thinking you have to be writing all the time to be "writing." Writing and a writer's life encompasses so much more than typing on your computer or putting pen to paper. It also involves doing research through books, the Internet, phone interviews, and face-to-face meetings; taking notes on any pertinent thoughts that happen to flow into your mind; learning more about your craft by studying other people's work that you love; and, most importantly, living a full and rich life because that, more than anything, translates to fuller, richer pieces of writing.