How to move object throught the waypoints in unity?

var FrontLeftWheel : WheelCollider;
var FrontRightWheel : WheelCollider;


var GearRatio : float[];
var CurrentGear : int = 0;

var EngineTorque : float = 600.0f;
var MaxEngineRPM : float = 3000.0f;
var MinEngineRPM : float = 1000.0f;
private var EngineRPM : float = 0.0f;


var waypointContainer : GameObject;
private var waypoints : Array;
public var currentWaypoint : int = 0;


private var inputSteer : float = 0.0;
private var inputTorque : float = 0.0;

function Start () {

    rigidbody.centerOfMass.y=-1.5;


    GetWaypoints();
}

function Update () {


    rigidbody.drag = rigidbody.velocity.magnitude / 250;

  
    NavigateTowardsWaypoint();

 
    EngineRPM = (FrontLeftWheel.rpm + FrontRightWheel.rpm)/2 * GearRatio[CurrentGear];
    ShiftGears();

    FrontLeftWheel.motorTorque = EngineTorque / GearRatio[CurrentGear] * inputTorque;
    FrontRightWheel.motorTorque = EngineTorque / GearRatio[CurrentGear] * inputTorque;

   
    FrontLeftWheel.steerAngle = 10 * inputSteer;
    FrontRightWheel.steerAngle = 10 * inputSteer;
}

function ShiftGears() {

    if ( EngineRPM >= MaxEngineRPM ) {
        var AppropriateGear : int = CurrentGear;

        for ( var i = 0; i < GearRatio.length; i ++ ) {
            if ( FrontLeftWheel.rpm * GearRatio[i] < MaxEngineRPM ) {
                AppropriateGear = i;
                break;
            }
        }

        CurrentGear = AppropriateGear;
    }

    if ( EngineRPM <= MinEngineRPM ) {
        AppropriateGear = CurrentGear;

        for ( var j = GearRatio.length-1; j >= 0; j -- ) {
            if ( FrontLeftWheel.rpm * GearRatio[j] > MinEngineRPM ) {
                AppropriateGear = j;
                break;
            }
        }

        CurrentGear = AppropriateGear;
    }
}

function GetWaypoints ()
  {

    var potentialWaypoints : Array = waypointContainer.GetComponentsInChildren(Transform );
    waypoints = new Array();

    for ( var potentialWaypoint : Transform in potentialWaypoints )
     {
        if ( potentialWaypoint != waypointContainer.transform )
        {
            waypoints[ waypoints.length ] = potentialWaypoint;
        }
    }
}

function NavigateTowardsWaypoint () {

    var RelativeWaypointPosition : Vector3 = this.transform.InverseTransformPoint( Vector3(
                                                waypoints[currentWaypoint].position.x,
                                                transform.position.y,
                                                waypoints[currentWaypoint].position.z ) );




    inputSteer = RelativeWaypointPosition.x / RelativeWaypointPosition.magnitude;

    print(inputSteer);


    if ( Mathf.Abs( inputSteer ) <  0.5 ) {
        inputTorque = RelativeWaypointPosition.y / RelativeWaypointPosition.magnitude - Mathf.Abs( inputSteer );
       
    }else{
        inputTorque = 0.0;
    }


    if ( RelativeWaypointPosition.magnitude < 20 ) {
        currentWaypoint ++;

        if ( currentWaypoint >= waypoints.length ) {
            currentWaypoint = 0;
        }
    }

}