Members will volunteer when they have all the details about what is being asked of them. No one wants to accept a task that is open-ended, vaguely defined, or requires a large percentage of their free time.
Please be very clear and specific about the skills needed, if there is training available, whether this is a one-time job, or a repeating task, and how many hours the volunteer can expect to put in for PSA.
Instead of one tiime-consuming, labor-intensive job, can the task be broken into smaller components and given to 2 or 3 volunteers instead of one?
Is this a task that would be more efficient and fun if several people were working together?
Will the volunteer be supported by you (or the PSA leadership)? Who can the go to for support, questions, praise and guidance?