Ownership by staff is important. This approach pays off in the long run. Start small and build up, learning along the way. Build on the volunteering employees already do. Consider also the social issues or problems in your area.
Marketing is crucial.
Emphasise the benefits for staff, such as personal development and enjoyment. Start with staff who are already motivated. They will pass on their interest to colleagues and word of mouth is far and away the most successful way to recruit volunteers. Invite a speaker from the voluntary sector who can inspire interest and action. Spread the message through company newsletters, e-mail, intranet and noticeboards.