A system for assisting a user to build an image on a body structure wherein the system comprises: - a body structure comprising a plurality of coupling structures (5, 5', 5", 6, 6', 6") arranged on a base portion and being configured to receive a building element (4, 4', 4", 7, 7', 9, 9'), - an illuminator which is an illumination device configured to provide illumination of at least a portion of the body structure and hereby provide a number of illumination areas (12, 12"), whereby the system comprises - a control unit configured to be applied to select a subset of the coupling structures (5, 5', 5", 6, 6', 6") and initiate an illumination that enables a unique identification of the selected subset of the coupling structures (5, 5', 5", 6, 6', 6") to be established by means of the illumination wherein - the control unit is configured to select the subset of the coupling structures (5, 5', 5", 6, 6', 6") to be illuminated by the illumination device in such a manner that the illumination device provides illumination areas (12, 12") of a first selection of colours not constituting all colours of the image, wherein the control unit is configured to select the subset of the coupling structures (5, 5', 5", 6, 6', 6") to be illuminated by the illumination device in such a manner that the illumination device provides illumination areas (12, 12") of a single colour, characterised in that the control unit is configured to receive feedback from the user, when the user has finished inserting beads (4, 4', 4") of a single predefined colour, wherein the control unit is configured to hereafter illuminate coupling structures (5, 5', 5", 6, 6', 6") that have not been illuminated. - a body structure comprising a plurality of coupling structures (5, 5', 5", 6, 6', 6") arranged on a base portion and being configured to receive a building element (4, 4', 4", 7, 7', 9, 9'), - an illuminator which is an illumination device configured to provide illumination of at least a portion of the body structure and hereby provide a number of illumination areas (12, 12"), whereby the system comprises - a control unit configured to be applied to select a subset of the coupling structures (5, 5', 5", 6, 6', 6") and initiate an illumination that enables a unique identification of the selected subset of the coupling structures (5, 5', 5", 6, 6', 6") to be established by means of the illumination wherein - the control unit is configured to select the subset of the coupling structures (5, 5', 5", 6, 6', 6") to be illuminated by the illumination device in such a manner that the illumination device provides illumination areas (12, 12") of a first selection of colours not constituting all colours of the image, wherein the control unit is configured to select the subset of the coupling structures (5, 5', 5", 6, 6', 6") to be illuminated by the illumination device in such a manner that the illumination device provides illumination areas (12, 12") of a single colour, characterised in that the control unit is configured to receive feedback from the user, when the user has finished inserting beads (4, 4', 4") of a single predefined colour, wherein the control unit is configured to hereafter illuminate coupling structures (5, 5', 5", 6, 6', 6") that have not been illuminated.