The book by Professors Fajans and Falk (F&F) is very helpful, so I’ll refer you to their many rich and thoughtful tips on starting your first draft. Below are some of idea mixed in with the excellent suggestions of Professors F&F.
The zeroth draft.
Your initial draft is for you and you alone. It’s not the “first draft” you hand in to the prof. It’s something for you to start fleshing out and revising.
Get it down on paper. Now.
Your zeroth draft will not sing. It will not be beautiful. That’s what revision is for.
Techniques for doing the zeroth draft.
You can start ex niholo (from nothing, just use your thoughts), from blueprints (your outline), or from building materials (your research notes):
Start ex nihilo: start with free writing.
As F&F say, just start writing. Don’t worry about grammar, spelling, transitions, or organization. Just get your thoughts down. Later on, you can move things around, flesh them out, revise, and make things better.
Start with blueprinting: write from your outline.
Sit down each day to flesh out parts of your outline. Say “today I’m going to write Part II.A of the background section.” each day, work on one or more parts until you get the whole thing written. If you hit a bump and realize you’ll later have to add a source or flesh out an idea, then flag it, but keep writing! This is like building by starting with a blueprint.
Start with building materials: write from your notes.
When my research is substantially complete, I’ll take my notes (which are initially organized by source) and copy them into a new document. In that document, I’ll start re-organizing the notes by issue/sub-issue rather than by source. I eventually paste all the random quotes and ideas from various sources into the relevant parts of my outline. Then I flesh those quotes and ideas into actual law review text.
Combine the methods.
Note that you can — and should — combine the three techniques. Sometimes I work from my current thinking, sometimes from the outline, and sometimes by shuffling and organizing my research notes. Usually, I combine all three methods.