As you see from this website, we have a few main menu items titled in one or two words, each of these menu items contains information plus sub menu pages. The Newsletter is probably the best example.
Yearly events start off on a page of their own but as years go by you either need to add information above and end up with a really really long page or delete last year's information and reports and so lose club history which is a shame.
Creating a sub menu
Go to the main menu page you want to create the sub menu from.
Use the new sub menu icon give the new page a title (1-3 words) plus a description for the hover text - you will notice if you hover the mouse over the sub menus at the side that hover text appears at the top of the column, this information is useful to both your reader and the search engines and save you using a very long title for the page name.
A new page will appear, save it and then start adding content.