How to show an occurrence to the client

Step 1: Make sure the client is invited
The client has to be invited to the project with the Client role: How to invite someone to your project.
Step 2: Turn on Visible to Client
When you register the occurrence, or when you edit it, turn on Visible to Client: How to register an occurrence. This switch is for the project owner and the engineer; for team members it's locked. Turning it on doesn't show anything to the client by itself: it only makes their name appear under Who to Notify.
Step 3: Tag the client
Under Who to Notify, tap the client's name to check it: it isn't checked by default. The name may show as the first part of their email address. This tag is what makes the occurrence show up for the client. If they've already created their account, they also get a notification.
Step 4: Save and check
Tap Register Occurrence, or Save Changes when editing. The client finds the occurrence in the Client Portal, under the Occurrences menu, and can follow it until it's resolved. Clients can't resolve or delete occurrences.
Step 5: To hide it again
Edit the occurrence and turn off Visible to Client: the client is removed from the tagged list and no longer sees the occurrence. Only the person who registered it and the project owner can edit it, and only while it is open: How to edit or delete an occurrence.

Step 1: Make sure the client is invited