If you don't like what the Word team set for you and prefer a different look for text, you can change the default character formats that Word uses for the Normal style. The program then uses the new formats in all new documents that you create from the current document template.  

Generally, when writing a letter, we only use one type of lettering for the entire document.  However, if we were writing a book or report, we would probably want our headings, or, titles to be different from the body of the topic, or we might even need to create a table of content.  It is far better to use the style feature, then set each line manually.  That way, if you decide at the end of the work that you want the headings set bigger or bolder, you only need to change the style attribute and all the lines set to that style will change throughout the document.  Almost like magic.

Change the default character formatting

1. From the Format menu, choose Font.

2. Do any of the following: 
    Set a new default font, type or select a font name in the Font box.
    Set a new default font size, type or select the new size in the Size box.
    Set any other formats you want to include for the new default settings, see Font

3. When you finish changing the character formats, click on the Default button at the bottom of the window.

4. When Word displays a dialog box asking you to confirm that you want to change the default font for the current template, choose the Yes button.

Word immediately applies the new formats in the current document. If Word later asks you to confirm changes, choose the Yes button again.

Word bases the defaults on the settings on both the Font and Character Spacing tabs. When you choose the Default button on either tab, Word uses the settings from both tabs for the new default settings.
 

Tip

To quickly change the default formatting, select text that has the formats you want. Choose Font from the Format menu, and then choose the Default button.
 

Creating a Style

When you create a style, you select the formats you want to apply with the style and give that particular group of formats a style name. A style can include any of the text formats that you can apply with a menu command, shortcut keys, or a toolbar button.

To create a paragraph style, format a paragraph to look the way you want it and use that paragraph as an example of the style formatting.
 

Create a paragraph style from sample text

1. Select a paragraph and apply the formats you want to save as a style.

2. On the Formatting toolbar, click in the Style box .
 

3. In the Style box, delete the current style name, type a new name, and then press ENTER.

Note:  When you create a paragraph style by using selected sample text, Word defines the style to have the font, size, and other character formats of the first character of the selected text.
 

Create a style by using the Style command

1. From the Format menu, choose Style.

2. Choose the New button.

3. In the Name box, type a name for the new style.

4. In the Style Type box, select the type of style you want to create.

By default, Word bases a new style on the style applied to the selected paragraph. To base the new style on a different style, select the style from the Based On box.

To apply a different style to the paragraph that follows the paragraph with the new style, select the style from the Style For Following Paragraph box.

5. Choose the Format button, and then select the formats to be applied by the style.

6. Choose the OK button to define the style.

7. Repeat steps 2 through 6 to create additional styles.

8. Choose the Close button to close the Style dialog box.