Sri Swamiji said,

It should be understood that pratyahara means withdrawing the mind from the objects of sense experience, then the senses function according to the mind, and not vice versa. The capacities of smell, taste, sight, touch and hearing are withdrawn from their objects and then the senses begin to follow the mind inward and not outward. This is withdrawal of the mind from the sense activities so that the sense organs also become introverted with the mind; they imitate the mind and follow it inside.

This is his description of pratyahara.

A simple way to practice basic Pratyahara is to be still. It is called Kaya Sthairyam. One has to be physically still and in a comfortable state of the body and the mind. One observes the body, the movements of the body and allow the body to be relaxed. One creates this condition and the mind accepts it. No effort is required and no advising the mind or body. Such a state will enable one to still the senses.

Aim Hrim Klim