If this is a document that you are opening and printing then a Date field will update when the document is opened as it reads the system date from the computer. For tomorrow's date, you need a calculated date field and that is covered by Paul Edstein's excellent work on dates linked from
Insert a past or future date
The example shows a Delay of 14 days and refers to the CREATEDATE field (which would be appropriate if the document was a template and you were creating new documents each time) Change the instances of CREATEDATE to DATE and the Delay to 1.