Method for assembling a main segment of a shoulder strap with figure-of-eight ring, comprising the steps according to which: a) a figure-of-eight ring with two slits (8, 9) is held according to a fixed initial position, with a first slit oriented transversely and downstream, and with a second slit oriented transversely and upstream relative to a direction of advance, b) an intermediate section of a band upstream of the figure-of-eight ring is caught by means of a mobile transfer clamp, and the band is displaced in the downstream direction with the aid of said transfer clamp to bring its downstream end section parallel to and facing the figure-of-eight ring, with its free end away from, in the downstream direction, the figure-of-eight ring, c) the downstream end section of the band is introduced into the first slit of the figure-of-eight ring by pushing using an introducing finger, d) the introducing finger is withdrawn and the figure-of-eight ring is pivoted by 180° in a first direction about the central crossmember of the figure-of-eight ring, so as to bring the downstream end section of the band downstream of the figure-of-eight ring, e) the downstream end section of the band is introduced into the second slit of the figure-of-eight ring by pushing using said introducing finger, f) the introducing finger is withdrawn and the figure-of-eight ring is pivoted by 180° about the central crossmember of the figure-of-eight ring in the second direction of rotation, to engage the free end of the band against the upstream lap of band upstream of the figure-of-eight ring, g) the free end of the band is secured to the upstream lap of band, h) a length of band is pulled in the downstream direction by a transverse stretching finger engaged on an intermediate portion of band between the figure-of-eight ring and the upstream lap of band, i) a ring is engaged parallel between the figure-of-eight ring and the upstream lap of band, and it is held facing the figure-of-eight ring, j) the band is cut upstream of the figure-of-eight ring, producing an upstream end section of band, k) the upstream end section of band is introduced into the ring and into the second slit of the figure-of-eight ring, using said introducing finger, l) said introducing finger is withdrawn, the upstream end section of band is immobilized, and the ring is moved in the downstream direction by sliding on the band, m) the figure-of-eight ring is pivoted by 180° in the second direction of rotation about its central crossmember, n) the upstream end section of the band is introduced into the first slit of the figure-of-eight ring using said introducing finger, and the main shoulder strap segment thus produced is released. a) a figure-of-eight ring with two slits (8, 9) is held according to a fixed initial position, with a first slit oriented transversely and downstream, and with a second slit oriented transversely and upstream relative to a direction of advance, b) an intermediate section of a band upstream of the figure-of-eight ring is caught by means of a mobile transfer clamp, and the band is displaced in the downstream direction with the aid of said transfer clamp to bring its downstream end section parallel to and facing the figure-of-eight ring, with its free end away from, in the downstream direction, the figure-of-eight ring, c) the downstream end section of the band is introduced into the first slit of the figure-of-eight ring by pushing using an introducing finger, d) the introducing finger is withdrawn and the figure-of-eight ring is pivoted by 180° in a first direction about the central crossmember of the figure-of-eight ring, so as to bring the downstream end section of the band downstream of the figure-of-eight ring, e) the downstream end section of the band is introduced into the second slit of the figure-of-eight ring by pushing using said introducing finger, f) the introducing finger is withdrawn and the figure-of-eight ring is pivoted by 180° about the central crossmember of the figure-of-eight ring in the second direction of rotation, to engage the free end of the band against the upstream lap of band upstream of the figure-of-eight ring, g) the free end of the band is secured to the upstream lap of band, h) a length of band is pulled in the downstream direction by a transverse stretching finger engaged on an intermediate portion of band between the figure-of-eight ring and the upstream lap of band, i) a ring is engaged parallel between the figure-of-eight ring and the upstream lap of band, and it is held facing the figure-of-eight ring, j) the band is cut upstream of the figure-of-eight ring, producing an upstream end section of band, k) the upstream end section of band is introduced into the ring and into the second slit of the figure-of-eight ring, using said introducing finger, l) said introducing finger is withdrawn, the upstream end section of band is immobilized, and the ring is moved in the downstream direction by sliding on the band, m) the figure-of-eight ring is pivoted by 180° in the second direction of rotation about its central crossmember, n) the upstream end section of the band is introduced into the first slit of the figure-of-eight ring using said introducing finger, and the main shoulder strap segment thus produced is released.