To add a menu on your Wordpress.com site we've added a convenient short-code to your customization dashboard. If you do not know if you're using Wordpress.com, or Wordpress.org, this article will help.
Login to grab the short-code for your menu:
Click Customize menus on the sidebar
Then select Website from the menu on top
Copy and paste the shortcode into the Wordpress.com page where your menu should appear. Save, publish, and enjoy your beautiful new website menu.