Add a custom domain
Two CNAMEs: script hostname and dashboard hostname. Paste each target from the Domains card, then verify.
Open Domains
Sign in and open /app/agency/domains. Script and dashboard hostnames are two separate cards. Domain last.
Two cards, not one host
Tracking script hostname: enter host, Save, add the CNAME, Verify script CNAME. Client dashboard hostname uses the same three steps and its own target on that card.