Buffer lets you easily schedule posts to multiple social accounts when you are working in the Day view and using the composer at the top of your screen.
You won’t be able to schedule posts for multiple social accounts if you’re within the calendar view (weekly or monthly) or if you choose a specific time slot in the queue, since those slots are designated for that specific social account and posting schedule.
If you are in the calendar view, click Back to Buffer Dashboard to get to the Day view, and then open the composer at the top of the queue.
When working inside the composer, simply click each social account that you want the post to be scheduled to. As you make your selections, accounts will be colored. Accounts that are not selected will remain uncolored.
For guidance on customizing your post for each social network, as well as scheduling options, hop over to this guide.
After you've scheduled the posts, they become separate from each other. If you need to make edits or delete the post, you will need to make those changes for each post in each social account queue.