The email that you've created can be shared across your social channels. BOMA cleverly hosts it as a landing page so it can be easily shared.
All you have to do is copy the link from the Review and Edit window from Email tab, after you've created your email - refer to the image below.
Copy the link and paste the URL as a link share. If you're not familiar with link share here are the instructions.
Remember to copy the link before sending your email.