After launching Big Lister you will see the Home Screen. The Home Screen lists sets of all the bird families in alphabetical order. If you are trying to find Barn Owls for example you would want to tap Accentors to Berrypeckers to find them. The tricky part here is that some birds have common names that are not indicative of the family they are in. For instance the American Robin is part of the Thrushes family and the Blue Jay is part of the Crows. Barn Owls and Cormorants on the other hand are easy.
Another method to get to the Blue Jay entry is to type the name into the Search Bar.
At the top right hand side is the My Lists button. Tap it to get to any lists you may have created.
At the top left hand side is the Preferences button. Tap it to configure the app to display different kinds of lists and for alternative ways to display those lists.