Lectern is a simple theme with a choice of standard Toastmasters banners that can be displayed as the page header.
This is one of the themes that allows you to change the main menu and several other options with the WordPress theme Customizer, which you access by clicking on Customize on the black bar that appears when you are logged in as a site administrator.
When you click Customize, a menu of options appears side-by-side with a preview of your website where you will be able to see changes take effect. For example, the Colors tab allows you to change the background color of your pages. Background Image allows you to specify an image instead. Site Identity is for changing the site title and tagline.
Edit the Main Menu (Customizer Method)
To add a page to the main menu, click on Menus and then Primary Menu.
To add an item, scroll through the list of pages and click on the + sign to add one to the end of the menu. You can also type in the title of a new page and click Add to add a new (blank) page that you can fill in later. Or you can add custom links, blog posts, or blog categories that you want to provide easy access to.
Drag and drop menu items up and down the list to change the menu order. You can also create a submenu (drop-down menu) by indenting one or more items under another. In the example above, Club Rules would appear under Members.
Change the Toastmasters Banner
Clicking into the Header Image section allows you to select between several standard Toastmasters banner images.