There is a map of the area and a sign for the start of the walk at the campground. Since this walk is a loop track, start in whichever direction you’d like when the track splits.
Taking the left side of the fork, you will be closer to the water of the Puhi Puhi River, while the right track is flanked by forest. The furthest point of the track reaches the Puhi Puhi River close to the Puhi Puhi Bridge which you will have gone over when driving to the start of the walk.
You may be able to hear the water rushing by during your walk but the majority of your time will be spent gazing at the trees and not at the water. Matai and kahikatea trees are found in the Puhi Puhi Scenic Reserve and some are estimated to be over 1000 years old. They are huge trees so there’s no way to miss them!