This hike starts at the ugly concrete baby dinasaur. It is located if you follow the road downhill from the train station. This road will end at T where you go down or up; down to the road to Trient or to Emosson dam.
Walk towards the baby dinosaur and you will see a path down to the train track. Cross the track and there is a well marked train down the mountain all the way to the river. This descent is nice but on the steep side, wherever it is steep, there are adequate rails for protection. I think there is only one section. Nothing is scary or sketchy. You don't want to do this hike in the rain as the river might be prone to flash flood.
Once you reach the river, just follow down where the water flows. There is a trail that goes to the border and beyond to France. There is an ancient forest untouched here. This trail either goes to Trient or all the way to Vallocine and to Argentiere and to Chamonix. The trail goes and goes.
At Gietroz, you can take the train back to Finhaut if you like. From here, the trail will be flat but is very pleasnt. You can also take train back from Vallocine. Between Vallocine and Argentiere, there is a small pass and it is bit far. Next station is called Planet Montroc.
If you want an easy and orientation hike, the first leg of the hike is good enough.