There is a quick way for you to invite to classmates or other alumni in through social media channels.
Click on Invite Alumni from under your name on the Main Menu.
This opens up a page listing the social media accounts that you can use to invite.
Click on Invite/Import next to the corresponding social media icon.
LinkedIn/Twitter lets you share an update/tweet. Facebook lets you message friends.
You can also import your contact list from Yahoo or GMail to mail your friends.
Pro Tip: A few weeks after your launch, it's a great idea to get your alumni to use the invite tool themselves. Encourage Class Agents or volunteers to start off, or send out an email to alumni telling them to use the invite tool to help your cause.
This way you can crowdsource more people to sign-up on the platform