Using the Search Box at the top of the page Search App Directory for Incoming
Webhooks. Click on Incoming Webhooks when prompted with the Incoming Webhooks
suggestion
Click Add Configuration
Select which channel you want to link the webhook to and then click Add Incoming
Webhooks Integration
Copy the Webhook URL
Switch back to the GorillaStack, provide a name to identify the Slack Channel and paste
the webhook URL into the Webhook URL field