1. An interactive method of presenting information in an image to a user within surroundings, using a system in which the user carries a head-mounted display device which presents an image of the surroundings to the user, said system operating in accordance with at least one chain of information having associated manipulations arranged in at least one chain of execution that is performed by a user in a hierarchical sequence of steps to complete a task, said method comprising the steps of: establishing the user's head position and direction in relation to the surroundings; establishing, by a calculating device of said system based on the user's head position and direction, which part of the surroundings is positioned in front of the user's head as well as the user's direction of gaze; establishing, by the calculating device, where the user is in a chain of information about the part of the surroundings that is positioned in front of the user's head, and where the user is in a chain of executed operations as regards the same part of the surroundings; establishing, by the calculating device, on the basis of where the user is in the chain of information and where the user is in the chain of executed operations associated with said part of the surroundings, which information in the hierarchical sequence is next to be presented to the user and presenting the information in the form of a virtual image which is mixed with a real image as a mixed image that enables the user to perform a current operation as a next step within the hierarchical sequence for completing the task; defining a central part of the mixed image, an area outside the central part including fields and/or objects that are shown in a way that is not disturbing to the user until the user's direction of gaze has left said central part of the image and that are adapted to be included in a transfer of messages from the user to the calculating device, said transfer of messages enabling the user to move back and forth in the hierarchical sequence to obtain information needed to perform the current operation; and the calculating device being informed that the user has received the information and, respectively, performed the current operation based on how the user's direction of gaze is positioned in one or more of the fields and/or objects such that the user, by changing the user's direction of gaze, initiates said transfer of messages to the calculating device; recognizing, by said calculating device, said transfer of messages and establishing, in response to said transfer of messages, which information in said chain of information is next to be presented to the user to enable the user to perform a next step within the hierarchical sequence; and presenting, by the calculating device, information relating to the next step in said hierarchical sequence making up said chain of executed operations for performance by said user to complete said task.