Your post will export with an automatic Table of Contents when you set $blogTOC to some whole number greater than zero. The number will determine the number of outline levels the Table displays.

If blogTOC is not visible on top of the text view among your key attributes, run the stamp.

If the children of your post have their $DENum set to true, then the headings will be numbered. Numbering in the Table of Contents is controlled separately—if you would like your Table of Contents to be numbered, just add NUM to the $blogExpOpt of the (parent) post.