fix(edge): fixed todo

Author: RoRoJ

pages/edge-services/reference-content/assets/scaleway-waf-add-on.webp

@@ -55,14 +55,16 @@ We provide a number of ways to keep track of your Edge Services consumption:
 
 ## WAF add-on
 
-The Starter plan is the only plan that does not include WAF. To use WAF on this plan, you must may an additional monthly add-on charge (see [pricing page]([pricing page](https://www.scaleway.com/en/pricing/network/#edge-services)). 
+The Starter plan is the only plan that does not include WAF. To use WAF on this plan, you must pay an additional monthly add-on charge (see [pricing page](https://www.scaleway.com/en/pricing/network/#edge-services)).
+
+To add the WAF add-on to your Starter plan, simply [enable WAF](/edge-services/how-to/configure-waf/) on a pipeline. You are then prompted to accept the add-on. You must pay the add-on charge in order to use WAF on the Starter plan.
+
+<Lightbox src="scaleway-waf-add-on.webp" alt="A screenshot of the Scaleway console shows that the user is prompted to tick a box to accept the WAF add-on when enabling WAF on pipeline, under Starter plan." />
 
 This add-on then lets you enable WAF on all your pipelines, and use a fixed amount of WAF requests for that month across all pipelines. Any WAF requests that exceed this amount will be charged additionally, as described below.
 
 WAF is only compatible with Load Balancer origin pipelines, not with Object Storage bucket pipelines.
 
-TODO ADD INFO ABOUT HOW TO ACTIVATE AND IF IT IS COMPULSORY
-
 ## Included usage vs additional charges
 
 Additional charges apply when you either: