Right-click the EffectsList column in the row of the buffer where you want to insert the Send effect.
On the shortcut menu, click Insert Send. A Send effect is added to the buffer, with a default destination of Standard Environmental Reverb. A Standard Environmental Reverb Buffer must exist in the audiopath if you want this to be the destination. This is all you have to do unless you want to send to a different buffer.
To send to a different buffer, open the Effect Properties window for the Send effect.
Select the destination mix group from the drop-down list. All eligible mix groups in all audiopaths that have been opened in Audiopath Designer are listed.
To send to a destination in another audiopath that has not been opened, choose Other. The Edit GUID Dialog Box appears. Enter the GUID of the destination buffer, and click OK.