Keyword harvesting from automatic campaigns involves identifying search terms that generate relevant traffic and conversions, then adding those terms as keywords to your manual or controlled campaigns.
Review your search term reports regularly and prioritise queries that generate qualified leads, sales, or strong conversion rates. Add proven terms to relevant ad groups using appropriate match types, and use negative keywords to exclude irrelevant searches.
Avoid harvesting keywords based on clicks alone. Evaluate conversion quality, CPA, and revenue before scaling them. Also, check for keyword overlap between campaigns to prevent unnecessary competition and duplicated spend.