Scheduled Campaigns keeps two lists — campaigns published for a future send time, and drafts saved but never published. Start one with Create a campaign.
1
Scheduled and Drafts are two different things
Campaigns → Scheduled Campaigns is where campaigns wait before they go out, split across two tabs that mean genuinely different things. Scheduled holds campaigns you have already published with a future send time — everything about them is settled, so Delete is the only action left on a row, and the list runs in the order they will actually send with the Scheduled column showing when. Drafts holds campaigns you saved but never published, ordered by Last edited with the most recent first, and every row carries Schedule, Edit and Delete. The distinction is the whole point of the page — a draft never sends on its own, however finished it looks, until you schedule or publish it.
2
Give a draft a send time
Schedule on a draft row opens the Schedule campaign dialog — this is the moment a draft stops being a saved idea and becomes a real send. Pick a Date, a Time and a Timezone; the date picker won't offer days that have already passed, and the timezone is what decides when your chosen time actually arrives for your recipients. Timezone is a short list of the common business regions and starts on your own zone when it is one of them, so check it rather than assuming — the whole send hangs on it. The time still has to be in the future once date and zone are combined; a moment already past is rejected rather than sent immediately. Once it saves, the campaign leaves Drafts and appears on the Scheduled tab with its send time against it.
3
Editing, and what happens when the time comes
Edit reopens a draft in the campaign wizard, where you can rework the audience, the template and the send timing before anything reaches a customer — see Create a campaign for what each step of that wizard asks for. Only drafts can be edited; once a campaign is scheduled, Delete is all that remains, so changing your mind means removing it and building it again. At the scheduled moment the campaign drops off the Scheduled tab by itself and starts sending — from there on it is a running campaign, and you follow its delivery and read numbers on Campaigns overview.