Use any or all of the following methods to select cell font and style using the toolbars:
Click on the arrow to the right of the Font box to choose a font.
Click on the arrow to the right of the Size box to choose a size (or type a size directly into the Size box).
Click on the Bold, Italic, Underline and Strikethrough buttons to apply styling.
The Bold, Italic, Underline and Strikethrough buttons have two states: up and down. If the active cell shows a button down, the effect has been selected; up and the effect is turned off.
You can also choose fonts and font styles by using the menus.
See: