I don't know if I agree with Murray about students and written drafts. Sometimes students seem to revere their handwriting so much they can't bear to change a word. Getting a piece typed and double-spaced can, in that event, give them the necessary distance to revise.
I have some counter-intuitive advice for you. Figure out what your hang-ups are, and then go there. If you believe you can't write in longhand, in a notebook, you should give it a try. Do it in the same spirit as you might use if asked to brush your teeth with your off-hand -- just to see what it does to your synapses. Do it several days in a row and see what happens.
For many years I felt that I had to write everything out in a notebook, preferably in a cafeteria or a coffee shop, someplace with noise. I wrote in a notebook, and then I used a typewriter -- a typewriter! -- to work through several drafts. Only then did I move to a word processor.
Then I had to write a doctoral dissertation. I didn't have time to fuss around. I had 18-month-old twins; I had a teaching appointment at the University of Washington. I got up early in the morning, when the house was deathly quiet. I made coffee, I put a load of laundry in the washing machine, and then I sat down (behind the couch, in our living room) at my computer, turned it on, opened the file for my dissertation, and started typing. Well, rereading and typing. (The first pages, and the first chapter, then chapters, got lots of attention. Eventually, I had to let go of even this method and move deeper into the project. It was terrifying.) After a couple of hours, I printed out whatever I had gotten through that day, and when I marched off to the university to teach, I packed those pages along with me. When I had a chance (between classes, students papers, meetings, etc.) I tugged the pages out of my bag, reread them, and made more notes. Did I mention that I had 18-month-old twins when this process began? At 11:30, I met my husband and said twins at the park-and-ride. I took the stationwagon, and the girls, and he went to work.
It took about two years of inconsistent, spotty attention, groaning and moaning, and talking it through, and then it took six months of dedicated, daily attention (about four months off from teaching), and I had a 250 page book to turn in to my doctoral committee. I could tell you more stories.
I could tell you lots more stories. The point, however, is that I gave up my laborious habits of having the right notebook and pen. I just wrote. And it worked.