Here's how to edit a post that has already been published:

  1. Click on the post you want to edit
  2. Click on the ellipsis icon (•••) in the upper right corner of the post
  3. Then click Edit

4. Edit the post by performing the same steps you used to create the post. You can add or remove content as need, including media. When you're done, click Update Post.

And you're all set. That post will be updated with all of the edits you have applied. 

Please note: all edits are tracked in the Activity Timeline at the bottom of a Post.