Get a sketch going with the DS18B20s, then get a sketch going with Cayenne, then put both in a blender, and blend for a minute or two…
What are you using for an Ethernet or Wifi shield? The Cayenne code is very simple, so integration should not be difficult at all.
Let us know when you have the separate sketches working, and I can help you with integration if you get stuck.
Cheers,
Craig