Why not just press the spacebar instead of Tab?

Is it that you are unfamiliar with setting tabstops? Or that you are having
problems setting a tabstop to the length of a "space"? For setting tabstops,
your might look at:
http://office.microsoft.com/en-us/word/HA100341291033.aspx

The length of a "space" is more complex, especially if you are using a
justified alignment. In addition, tabstops are normally set as some distance
from your left margin. While some people use tabs at the beginning of a
paragraph as a first-line indent, it is generally better to create a first
line paragraph indent instead.

Steven Craig Miller