How can I move left and right when jumpigng?

Hello I just make a simple game from Unity 3D tutorials and I want to control the player (ball) when I jumping. Sorry for my bad englis, I beginner in this, too:)

I made this script:

 #pragma strict
 
 var rotationSpeed = 100;
 var jumpHeight = 8;
 
 private var isFalling = false;
 
 function Update () 
 {
      //Handle ball rotation.
      var rotation : float = Input.GetAxis ("Horizontal") * rotationSpeed;
      rotation *= Time.deltaTime;
      rigidbody.AddRelativeTorque (Vector3.back * rotation);
      
      if (Input.GetKeyDown(KeyCode.W)  && isFalling == false)
      {
          rigidbody.velocity.y = jumpHeight;
      }
      isFalling = true;
     
 }
 
 function OnCollisionStay ()
 {
     isFalling = false;
 }