Complex sentence: To achieve natural point of aim, the shooter settles into position with the eyes closed, opening them after ensuring the position is comfortable and the firearm is resting in the stance with minimal muscle tension.
Split into simpler sentences: To achieve natural point of aim, the shooter settles into position while not looking through he sights. The shooter looks through the sights only after ensuring the position is comfortable and the firearm is resting in the stance with minimal muscle tension.