From Microsoft Support web.

Visio: How to Make Hanging Indents in a Bulleted List

SUMMARY
When you make bulleted lists in Visio, the text wraps to the beginning of the paragraph, and the only way to get a hanging indent is to type manual line breaks. This document explains how to manually create a bulleted list with hanging indents.

MORE INFORMATION

To make a bulleted list with hanging indents, you must change the Indents settings in the Paragraph dialog box, and set a tab.

To set the indent and tab settings:

1. Select the text tool and draw a text block, or select a shape with the pointer tool or text tool.

2. On the Format menu, click Paragraph. [在Visio中，Format > Text... > Paragraph标签中]

3. Change the Horizontal Alignment setting to Left in the Paragraph dialog box.

4. In the Indents [在Visio 2003 中是Identation] section:
   Enter 0.25 for the From Left setting (or whatever value you want, but make sure that there is enough space for a "bullet" character and a blank space).
   Enter the same value for First Line, but make it negative, for example, -0.25 in. [这是保证自动换行后完全对齐]

5. Click OK to set the indent.

6. On the Format menu, click Tabs.

7. In the Edit Tab section, enter a Position setting in the Tabs dialog box using the From Left value from the Paragraph dialog box. In this example you would set the first tab at 0.25 in.

8. Click Apply to see the results, and then click OK to accept them.
   [7,8中提到的和Visio2003完全不一样]

After you have completed the steps, you can make a bulleted list by typing a bullet, and then pressing TAB before you type the text. If the text wraps to subsequent lines, it will wrap to the location of the tab, and the bullet will "hang" to the left, for example:

• Item one
  wrap to here
• Item two
  wrap to here, and so on.

NOTE: To make a standard bullet in Visio, press CTRL+SHIFT+8. In any other Windows-based program, press ALT+0149 (hold down the ALT key, and then type the numbers 0149 in the numeric keypad).