A method of printing a second document from a computer system is provided. The method makes use of a first document and a handheld optically imaging sensor. The first document includes an interface, the interface including visible textual information and substantially invisible first coded data in the form of one or more tags, each tag defining unique coded data identifying the first document and a position of that tag on the first document. The sensor generates indicating data indicative of the position of the sensor relative to the first document using sensed coded data. The method includes the steps of, in the computer system: (a) receiving the indicating data from the sensor; (b) determining the second document with which the indicating data is associated; and (c) causing the second document to be printed by a printer. The second printed document includes visible textual information and substantially invisible second coded data in the form of one or more tags, each tag defining unique coded data identifying the second document and a position of that tag on the second document.