Seek advice of your doctor/physiotherapist who is aware of the patient history. When using only one stick, hold it in the opposite hand to the affected leg preserving a natural walking pattern and an upright posture. The stick and the affected leg should move forwards together. Walking sticks are not often used by individuals with Parkinson’s disease as they tend to hold their sticks off the ground and should consult their doctors
Some walking sticks are made of wood, which can be measured and cut to the correct height adjusting for a ferrule if there is one
For metal sticks, nearest suitable height should be chosen. Most metal sticks and metal walkers/walking frames have a length adjustment mechanism with spring loaded catches using which one can adjust the required height.