From Rifugio Lavarella, head to Rifugio Fanes, and then SE over Passo di Limo. Pass Ucia de Gran Fanes (lunch opportunity), toward the end of an open, flat meadow, follow the signs to the left to head up and over Forcella del Lago. The route is quite visible from the turnoff.
From the Forcella, enjoy the views and then descend on the other side on a reinforced trail through the scree. Continue along the descending traverse just above the lake. After passing the lake, continue straight toward Rifugio Lagazuoi. Follow the trail that ascends gradually through a moonlike landscape.
Eventually Rifugio Lagazuoi comes into view. Follow the signs for Forcella Lagazuoi Rifugio Lagazuoi, turning left at a trail junction. At Forcella Lagazuoi, ascend the obvious switchbacks to the right to the rifugio.
If you are not overnighting at Rifugio Lagazuoi and are not descending via the War Tunnels or the Gondola, you can turn left here toward Forcella Travenanzes, where the descent trail to Passo Falzarego begins.