how do I save a web page to Safari (6.2.6) Reading List?

Open Safari for me

• Add a page to your Reading List: Move the pointer over the address and search field, then click the One-Step Add button that appears at the left end of the field. You can also Shift-click a link on a webpage to quickly add it.
• Show or hide your Reading List: Click the Sidebar button in the toolbar, then click the Reading List button at the top of the sidebar. To hide the list, click the Sidebar button again.
• Remove a page from your Reading List: Hold the pointer over the page summary in the sidebar, then click the Remove button that appears in the corner of the page summary.
• Search your Reading List: Enter text in the search field above the list of page summaries. You may have to scroll up to see the search field.
• Read the next page in your list: Keep scrolling when you reach the end of a Reading List page—no need to click the next page summary in the sidebar.
• Hide pages you’ve read: Click the Unread button above the list of page summaries. Click the All button to show pages you’ve read in your list. You may have to scroll up to see the buttons.
• Mark a page as read or unread: Control-click the page summary in the sidebar, then choose Mark as Read or Mark as Unread.

Welcome 🙂

Just so you are aware, that information is available from the Safari Help menu.

From your Safari menu bar click Help > Safari Help

Example: Type: Reading List in the search field.