The starting build
- Brand — its own campaign, always, so brand revenue is visible separately.
- Core products — your proven sellers, exact and phrase.
- Category terms — broader intent, tighter negatives.
- Discovery — a small budget on broader matching to find terms you had not listed.
What changes as you grow
Split out any product or category that accumulates enough conversions to bid on independently. Until then, keeping them together is what gives the bidding something to learn from.
What not to do
Single-keyword ad groups in a Smart Bidding account. They were a manual-bidding technique and they now split conversion data so thin that nothing learns.
The maintenance
Discovery feeds the other campaigns: terms that convert graduate into core, terms that waste become negatives. That loop is most of the job.