When the Main Window is open (pictured to the right), press the disclosure triangle in the lower left hand corner of the window (or press the "Add Words" button). The window will grow and reveal a text entry field (pictured below). The cursor will already be in the field waiting for your input. Start typing your words/phrases in this field and press return, enter, or tab to add the word/ phrase to your word list. The field will clear and be ready for your next word/phrase.