In case you missed it, you can edit your posts on Mastodon:

1. Go to the post you want to edit
2. Click ⋯ on the post
3. Select "Edit"

This works on the website interface, the third party apps and the official apps.

To avoid abuse of the edit feature, everyone who has interacted with the post will receive a notification to say it is edited, and a link will appear below the post which shows all previous versions.

You can also use editing to add text descriptions if you forget to do them.