Create a bone chain > Add an HI Solver. > Motion panel
Here are the controls to turn on and off a variety of gizmos in the viewport. The Goal and End effectors, the vector handle of the swivel angle manipulator, and the IK solver display itself, are all located in this rollout.

Controls the appearance of the end effectors in the IK chain. Off by default.
Enabled—Turns the end effectors display on or off.
Size—Controls the size of the end effector gizmo in the viewport.
Controls the appearance of the goals in the IK chain. On by default.