Hi dkuroda,
In the Webhooks trigger, you will find the Resume Guided Setup option. Click on it, and then click NEXT. The webhook will start listening for events.
Now, create or update an issue in JIRA.
If everything is configured correctly in JIRA, your Webhooks recipe should be triggered, and the schema will be automatically generated.
Once the schema is generated, you can start building your actions based on the incoming payload from the Webhook (which, by default, will come from JIRA).
NOTE: Please check the Webhook type before starting the recipe. My recommendation is to go with JSON Payload.
Also, Workato provides a native JIRA connector as well.