I hope you've followed — and enjoyed — the whole Before You Write thread. This is Part 3, and here's a link to Part 2 if you'd like to catch up.
So, here's the third big thing I think you need to do before you start writing, for real. You need to . . .
Act Like a Writer
(1) Set up a writing space. I know that it can be difficult to designate one whole room (or even a portion of a room) as your writing space. But do the best you can with this one. A dedicated writing space can put you in the right frame of mind, help keep you organized, and reinforce your attitude (others' attitudes too, if that's an issue) that this is a professional endeavor.
(2) Set a writing schedule and a number of writing goals for each project. Each writer works differently, but everyone can benefit from setting a schedule and some specific goals. Keep them both reasonable and attainable. Try to create your writing schedule based on when you know you do your best writing.
For example, I write every weekday morning, without fail. That's when my head is clear, and it's when I'm conditioned to dig in. When I first plan a writing project, I establish some general benchmarks, such as when the writing begins (post-research), when I need a working outline, and when I should have my own first draft (this should always occur well before the date you're scheduled to turn in a draft to your publisher).
I tend to set my daily goals on a case-by-case, day-by-day basis, but many writers stick to relatively hard-and-fast daily goals such as 3 pages per day, 1 chapter per day, writing with no interruptions for 4 hours per day, and so on. With practice, you'll find your own rhythm and be able to set realistic schedules and goals.
(3) Set the mood. Each time you sit down to write, do something that signals, to you, that it's time to get writing. You could play some music while you get situated, make one "last" phone call, or do one more household chore so you feel ready to go.
Now you're ready to write! I'll talk about the writing stage, too, in upcoming posts, so be sure to check back often.