Organizing with SDS at Columbia, I was exposed to a method that involved increasing our numbers through education, one-to-one contact, and occasional confrontation (see the first two chapters of "Underground"). This method was inherited from the Labor and Civil Rights Movements. It's been used by all successful social and political movements in this country.
There's been a break of more than a generation in the use of organizing, so the anti-Iraq war movement, for example, didn't know how to grow. Many well-meaning activists thought that if they just expressed themselves, holding up a sign on a corner, for example, others would join. But it doesn't work that way. Weatherman proved that: it was pure self-expression, not organizing.
This section has numerous essays on this problem and also historical examples of successful movement organizing. For a great case study, see the middle section of Barack Obama's first book, "Dreams From My Father," which is all about organizing on the streets of Chicago.
New Essay, appearing in Counterpunch, "What it Takes to Build a Mass Movement."