The prepare pose angle is the angle of the avatar's arms when in prepare mode. The default angle is 60 degrees. The angle is set away from the final pose angle to allow the simulation to complete. You might want to adjust this to give the simulation more time.
To change the prepare pose angle:
Ensure the garment has been arranged on the avatar. For more information, refer to How to Arrange Pieces.
On the Main menu, click 3D Environment.
Click Prepare Pose Angle. The available angles are displayed.
Click the angle you want.
When you click dress, the avatar dresses from the prepare pose angle and finishes when it reaches the final pose.