Fortunately we are not helpless before the barrage of sensory impressions. Pratyahara provides us many tools for managing them properly. Perhaps the simplest way to control our impressions is simply to cut them off, to spend some time apart from all sensory inputs. Just as the body benefits by fasting from food, so the mind benefits by fasting from impressions. This can be as simple as sitting to meditate with our eyes closed or taking a retreat somewhere free from the normal sensory bombardments, like at a mountain cabin.
Yoni mudra is one of the most important pratyahara techniques for closing the senses.
It is done for short periods of time when our prana is energized, such as immediately after practicing pranayama. Another method of sense withdrawal is to keep our sense organs open but withdraw our attention from them. In this way we cease taking in impressions without actually closing off our sense organs. The most common method, shambhavi mudra, consists of sitting with the eyes open while directing the attention within, a technique used in several Buddhist systems of meditation as well. This redirection of the senses inward can be done with the other senses as well, particularly with the sense of hearing.