Drag one of the small balls on the rotational axis to reorient the Move handle,
or dimension the orientation by typing the rotation angle while you are
dragging, then pressing Enter.
You can also Alt+click a point or line, or click the Move
Direction tool guide, then click a point or line, to orient one of
the Move handle's axes toward that point or along that line.
If you Alt+click a trajectory, you can move along the trajectory.
Ctrl+Alt+click to add contiguous lines or edges to the trajectory.
If you Alt+click a plane, the direction of movement is set perpendicular to
the plane.