Mamabear,
You add it as an effect into the effects box.
If you didn't see it as a possible effect, then you need to run "Scan VST Plugins"
under Tools->Cakewalk Plug-in Manager
If you don't see it after your scan, then you need to make sure it's copied
to the correct VSTPlugins folder under Cakewalk on your hard drive.
Chip