Button Add new at the bottom of the screen makes it possible to add new questions and answers to your collection:
To complete your item:
You can jump between the question and the answer by pressing Ctrl+T. If question and answer fields are inactive (e.g. after pressing Esc a few times), you can edit the question by pressing Q or edit the answer by pressing A. You can also start editing them with a click of the mouse. If you want to make both fields active at the same time, press Ctrl+E.