Hi Grace,

Thank you for your interest. I would recommend checking out the sites and needs listed NYC main page to find out where you can help. Once you find a site you are interested in, send a personal email to the site leader. As far as the Manhattan sites, you are welcome to help at either one, but they are both well-staffed at this point.
http://community.help-portrait.com/group/newyorkcity

Good luck,
Kaity