Our experience has consistently been that a generic call for volunteers rarely generates a response. The most effective tactic we’ve seen across all clients is a personal request from a board member with a very specific description of the task to be undertaken (i.e. what do you want me to do, how long will it take, when will I be done).
In most cases, the best approach may be incremental – in other words, rather than asking someone to take on a particular role for a year, ask someone to put together a lunchtime workshop for January (or some other specific month). Once they’ve performed the task successfully, they might be more inclined to take on more. Of course the other advantage of this approach is that the association isn’t on the hook with this individual beyond that date and can “test” the applicant before making a longer term commitment.