Prepare your hike, schedules, main points of passage, difficulty.
If you use public transport. allow a margin for the return schedule.
Book your place in the Mountain refuge if you intend to spend the night there.
With children aged 12 and under, add 50% of the time to the basic schedule. On the way up, the children walk in front of you and follow you downhill, always having an eye on it.
Beware of the weather, in the valley bottoms and above a certain altitude, the changes are sudden and storms very violent.
Tiredness can easily trip you, especially on the way back and downhill.