It occurs to me that ahead of the VSO event blogged below it might be of interest to look at the PDF here.  It essentially outlines the skill groups most needed.

It’s not exhaustive - as an example I knew a few VSO volunteers with hospitality and tourism skills.  In addition, though my background is journalism and PR I ended up a fundraiser.  I reasoned that fundraising was just publicising a lack of cash and what it was needed for. 

I guess I was half right but close enough.

Just remember everyone is there to teach.  The idea being that you don’t just do your job - you train someone else to replace you when you leave.   VSO will train you how to do this before you depart.