How can I draw a ray for direction object is moving?

Hi, I've been trying to get a ray to draw in the direction a cube is facing but I don't understand how. The reason I'm trying to do this is because I'm making a random moving AI that will rotate in a random direction and move forward.

Here is my code: if( counter <= 0){ counter = 100; dir = Random.Range(0,360); transform.eulerAngles=new Vector3(0,dir,0);

         print("change");
     }
     else
         counter --;
     Debug.DrawRay(transform.position,new Vector3(transform.position.x,transform.eulerAngles.y,transform.position.z));