add 2nd navigation menu on sidebar to hemingway rewritten

Hemingway rewritten only allows for one navigation menu. I would like to add another one to the side bar for a different set of blog categories. I would like to add sub menus to All Things Tarrywile and another on the left for wedding planning tips. Is there a way to walk me through adding code to the design? Thank you.

tarrywilemansion.com