Creation of a Web Application Firewall (WAF) is a one time process. Create a WAF in the AWS Console, fetch the ID/ARN and update the plan in DuploCloud. Once the plan has the WAF it can be used attached to the LB.
Analyzing inbound traffic with WAF dashboard
DuploCloud also provides a WAF Dashboard through which you can analyze the traffic that is coming in and the requests that are blocked. The Dashboard can be accessed from left navigation panel: Security > WAF.