As a documentarian, the footage is the goal.
And amazing footage is the thing.
So make FILMING your job
At least for about three months.
Block off 3 solid months for non-stop filming. And bada-bing. That's your movie.
Just accumulate massive amounts of quality footage.
Editing as you go along is fun, irresistible, and lets you know what you may or may not need to capture (I do it alllllllllllll the time).
However, after watching "Tracking Down Maggie" (1994), I'm starting to think I should leave the editing for a later date and focus on the filming.
Waking up, calling people, setting up meetings, driving to them, filming, more filming, planning, arranging, e-mailing, reflecting... Again the next day, and again the next.
If I can do this for three months, and put in the hours, and stick with the subject every day for three months... the creation of a great documentary seems inevitable.