In form design view, right-click the button and choose Properties.
Set Display When (Format tab of Properties sheet) to Screen only.
Quite honestly, the best solution is usually to design a report that looks
exactly how you want rather than print the form. For an example of how to
print just the current record in the form, see:
Print the record in the form
at: http://allenbrowne.com/casu-15.html