1. First open the word office software. Taking word20 13 as an example, I created a new blank document and marked it with titles at all levels.

2. Select-Start-Multilevel List in Paragraph

3. Select the number grading mode of the current list, and choose to define a new multilevel list.

4. Select More in the pop-up dialog box.

Secondly, set the numbering format.

1 and 1 level title numbers, as shown in the figure below.

2, 2 title number, as shown below

3, 3 level title number, as shown in the figure below, generally we also use 3 level titles.

4. Choose the format of titles at all levels.