Chip Pearson has some techniques that convert your input to dates at:
http://www.cpearson.com/excel/DateTimeEntry.htm

Helen wrote:

I have been trying to type the dates with this format mm/dd/yyyy, but I would
like not to do it everytime I want to insert a different date. I just want
to type the numbers, and that excel put the date format automaticaly without
me typing the // or formating it each time a put a different date.

--

Dave Peterson