This article explains how to schedule a Tweet.
Step 1: Log into www.twitter.com and navigate to one of the "Tweet" sections. See below outlined in red.
Step 2: Click on the calendar icon with the clock over it, see below outlined in red.
Step 3: Set the date and time you wish your scheduled Tweet to go out and click the "Confirm" button. Outlined below in red.
Step 4: If your schedule settings have been saved you will see them at the top of the Tweet (not shown when live) outlined below in red. Once you have written your "Tweet" click "Schedule", outlined below in red.
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