How do I create a group?

In order to create a group, you must be a Site Admin with write access. 

From the Configure Site page, you will see your site with a carrot to expand on the left. You can expand your site to see BACnet devices on your network. Click on a device and choose Create Group from Device to create a group with all objects in that device.

You can also click Create Group from the Groups List on the right to create an empty group.