How to scale a pdf: such as a survey

Hi.  I am getting hung up on how to resize a document such as a survey for a property.  For example:  if the scale on the survey says:  1" = 30' and it measures 1" = 20'.  I know how to change the scale ration and precision to where it will measure correctly on the pdf.  However I am trying to resize it so where when it prints, it prints to scale.  In other words I need the image/survey to be zoomed in when it prints, so it prints the proper size to be measured with a ruler.