The purpose of this thesis was to write an instruction manual to the users that are beginning to use Mitsubishi Electric GOT1000 -operation terminals. The manual will walk you through from the initial start of the operation terminal all the way to the creation of a remote connection. The aim of the manual was to create a document that is clear and consistent so that after the user has read the manual through, he or she undestands the basic functions of the operation terminal and can independently apply the theory of the instruction manual.

The theoretical part of the thesis introduces the concepts of the human machine interface and the operation terminal. It also goes through the grammatical, typographical and visual elements that are required in a good instruction manual. Finally it introduces the facts that you should pay attention when testing an instruction manual.

The implementation part of the thesis will walk you through the aim and the contents of the instruction manual, sections of writing it and implementation of a one section in the manual. In addition it figures out how the elements of a good instruction manual take place in this particular manual and it ponders the result of the test of the instruction manual.