To change the font size, follow these steps:
1.On the Home tab, in the Font group, click the arrow to the right of the size of the current font.
2.In the list that expands, select the desired font size.

If the required size is not on the list, you can set it manually. To do this, proceed as follows:
1.On the Home tab, in the Font group, select the current font size value.
2.Enter the required value. Use a dot (.) as a delimiter for fractional values. For example, 21.5.
3.Press Enter.
To change the font size by one point, on the Home tab, in the Font group, click
Increase font size or
Decrease font size.