Descriptions of the Aiki-taiso from Rod Kobayashi-Sensei:
13. Sayu Enkei Undo
Standing naturally with your arms at your sides, the "One" count has you turn 90 degrees to your right and complete the Enkei-undo with the count "Two" with your left hand. Immediately return to face the front and repeat it on your left side.
Repeat this exercise several times, alternating right and left.
This exercise is to open the door for the oncoming attacker to allow you to lead them while well within your range of effectiveness.