def METHOD_NAME(self):
    # Set up main window
    self.main_window = toga.MainWindow(title=self.name)
    # register fonts
    toga.Font.register(
        "awesome-free-solid", "resources/Font Awesome 5 Free-Solid-900.otf"
    )
    toga.Font.register("Endor", "resources/ENDOR___.ttf")
    toga.Font.register("Endor", "resources/ENDOR___.ttf", weight=BOLD)
    toga.Font.register("Endor", "resources/ENDOR___.ttf", style=ITALIC)
    toga.Font.register("Endor", "resources/ENDOR___.ttf", weight=BOLD, style=ITALIC)
    toga.Font.register("Roboto", "resources/Roboto-Regular.ttf")
    toga.Font.register("Roboto", "resources/Roboto-Bold.ttf", weight=BOLD)
    toga.Font.register("Roboto", "resources/Roboto-Italic.ttf", style=ITALIC)
    toga.Font.register(
        "Roboto", "resources/Roboto-BoldItalic.ttf", weight=BOLD, style=ITALIC
    )
    # Buttons
    btn_box1 = toga.Box(
        style=Pack(direction=ROW, padding_bottom=10),
        children=[
            toga.Button("Clear", on_press=self.do_clear),
            toga.Button("Weight", on_press=self.do_weight),
            toga.Button("Style", on_press=self.do_style),
        ],
    )
    btn1 = toga.Button(
        "Monospace",
        on_press=self.do_monospace_button,
        style=Pack(font_family=MONOSPACE),
    )
    btn2 = toga.Button(
        "\uf0c5",
        id="copy",
        on_press=self.do_icon_button,
        style=Pack(font_family="awesome-free-solid", font_size=14, width=50),
    )
    btn3 = toga.Button(
        "\uf0ea",
        id="paste",
        on_press=self.do_icon_button,
        style=Pack(font_family="awesome-free-solid", font_size=14, width=50),
    )
    btn4 = toga.Button(
        "\uf0a9",
        id="arrow-right",
        on_press=self.do_icon_button,
        style=Pack(font_family="awesome-free-solid", font_size=14, width=50),
    )
    btn_box2 = toga.Box(
        style=Pack(direction=ROW, padding_bottom=10),
        children=[btn1, btn2, btn3, btn4],
    )
    # Labels
    lbl1 = toga.Label("Endor", style=Pack(font_family="Endor", font_size=14))
    lbl2 = toga.Label(
        "Endor bold",
        style=Pack(font_family="Endor", font_size=14, font_weight=BOLD),
    )
    lbl3 = toga.Label(
        "Endor italic",
        style=Pack(font_family="Endor", font_size=14, font_style=ITALIC),
    )
    lbl4 = toga.Label(
        "Endor bold italic",
        style=Pack(
            font_family="Endor",
            font_size=14,
            font_weight=BOLD,
            font_style=ITALIC,
        ),
    )
    lbl5 = toga.Label(
        "Roboto",
        style=Pack(font_family="Roboto", font_size=14),
    )
    lbl6 = toga.Label(
        "Roboto bold",
        style=Pack(font_family="Roboto", font_size=14, font_weight=BOLD),
    )
    lbl7 = toga.Label(
        "Roboto italic",
        style=Pack(font_family="Roboto", font_size=14, font_style=ITALIC),
    )
    lbl8 = toga.Label(
        "Roboto bold italic",
        style=Pack(
            font_family="Roboto",
            font_size=14,
            font_weight=BOLD,
            font_style=ITALIC,
        ),
    )
    unknown_style = dict(font_family="Unknown", font_size=14)
    lbl_u = toga.Label("Unknown", style=Pack(**unknown_style))
    lbl_ub = toga.Label(
        "Unknown bold", style=Pack(font_weight=BOLD, **unknown_style)
    )
    lbl_ui = toga.Label(
        "Unknown italic", style=Pack(font_style=ITALIC, **unknown_style)
    )
    lbl_ubi = toga.Label(
        "Unknown bold italic",
        style=Pack(font_weight=BOLD, font_style=ITALIC, **unknown_style),
    )
    self.textpanel = toga.MultilineTextInput(
        readonly=False, style=Pack(flex=1), placeholder="Ready."
    )
    # Outermost box
    outer_box = toga.Box(
        children=[
            btn_box1,
            btn_box2,
            lbl1,
            lbl2,
            lbl3,
            lbl4,
            lbl5,
            lbl6,
            lbl7,
            lbl8,
            lbl_u,
            lbl_ub,
            lbl_ui,
            lbl_ubi,
            self.textpanel,
        ],
        style=Pack(flex=1, direction=COLUMN, padding=10),
    )
    # Add the content on the main window
    self.main_window.content = outer_box
    # Show the main window
    self.main_window.show()