Are you using the hanging indent command (Ctrl + T)?

You first need to set your tab stops correctly for your numbers, then a stop where you want text to begin after numbers. Ctrl + T sets the indent stop for you.

Try this:

Type A:
Press Ctrl + T, then press Tab
Type 1.
Press Ctrl + T, then press Tab
Type text, pressing Enter at end of sentence.

For #2,
Press Tab, type #2, Tab, and text will auto align.

#3 and subsequent numbers will auto format to align with #2 if auto numbering is turned on.

This format will stay in effect until you press Ctrl + Shift + T again (if you choose to). Be very careful editing, particularly with the Backspace key or spacebar -- you may want to show tab and paragraph marks so you don't wipe out the formatting.