As one man can defeat ten men, so can one thousand men defeat ten thousand. However, you can become a master of strategy by training alone with a sword, so that you can understand the enemy’s stratagems, his strength and resources, and come to appreciate how to apply strategy to beat ten thousand enemies.
You must be in a place where man-made objects such as buildings, towers, castles, and such do not obstruct your view, as well as facing or standing in a position where the sun or moon does not affect your vision. This is purely so that your vision is focused on nothing but the enemy, and thus there is more concentration upon the enemy’s stratagems.
You must look down on the enemy, and take up your attitude on slightly higher places.