The ad schedule controls when ads run, by day of week and hour ranges, each with an optional bid modifier.
Businesses that answer the phone - if leads only convert when someone picks up, weight budget into staffed hours rather than paying full price for a 2am click.
Emergency/24-7 services - the opposite: run around the clock, and consider bidding up overnight when competitors have gone dark and an emergency caller converts at the highest rate of the day.
Everyone else - start without a schedule, then let the hour-of-day data tell you where to trim.
How to set one:
Add day + hour ranges for when ads should run.
Optionally attach a bid modifier to each range.
Set the start date (defaults to tomorrow) and an end date only if the campaign is genuinely time-boxed (a sale, an event).
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