To access the main lists, you can select any of the main menu items:
or
Hovering over these top level menu items for a second will auto-expand that menu to provide more options, for example the main Clients lists can be accessed by hovering over the top level item to reveal further options, and then clicking any of those options to view that list:
Top Tip: If you have previously filtered a list or are currently working with a particular Saved View, then clicking the top level main menu item, in this case:
...will return you to the last list you were viewing so will not apply any automatic filters. This is particularly useful if you are navigating away from the list to open records and wish to return to the list again.