The method comprises positioning a first blade (10A) in substantially vertical position, connecting first ends of a first and a second cable section (24, 26), respectively, with a structure included by the nacelle (6), connecting second ends (30) of the first and the second cable section (24, 26), respectively, with the repair platform (18) and lifting the repair platform along said blade (10A) by means of the first and second cable sections (24, 26). The first and second cable sections (24, 26) are positioned so that they extend over the hub (8) and are supported at a distance from each other between root regions (16) of a second and a third blade (10B, 10C), respectively.