Hi,
You can create a new list or use the list that you already created. Select
the first item in your list. On the Home tab of the Ribbon, in the Paragraph
group, click the arrow next to the simple Numbering button, and then click
Define New Number Format. In the Define New Number Format dialog box, click
anywhere in the Number Format text box and type the number 1 and a period
(1.). At this point, you should see only 1. in this box. Next, click the
arrow of the Number Style drop-down box and select 1,2,3... . Now press Tab
twice to navigate back to the Number Format Text box and type a period (.).
You should now see 1.1. in this box. Click OK. At this point your list should
be numbered 1.1., 1.2., 1.3., etc. Again, on the Home tab of the Ribbon, in
the Paragraph group, click the arrow next to the simple Numbering button, and
then click Set Numbering Value. In the Set Numbering Value dialog box, change
the number in "Set value to" to 0 and click OK.
