2 ubiquiti switches, 2 separate networks, 1 sonicwall tz400

Hi,

I have 2 separate networks at a clients office, one for phones and one for data. I have 1 uniquiti cloudkey and 2 ubiquiti switches. I need the 2 switches to be added to the portal for management, but I only have 1 cloudkey, so I need to find a way to get these 2 switches to be able to communicate with each other so I can have them both online on the portal at once. One network will be on a class C range and the other a class B range.

My thoughts were to connect the data switch to the lan port (x0) on the back of the sonicwall, the data router to x1, configure x2 on the sonicwall to be another lan interface for voip switch, and the x3 to be a WAN interface for for voip router.

What config would I need to do to make this work? Is my thinking right?

Thanks!