how to create instance in Unity

using UnityEngine;
using System.Collections;
 
public class Car : ScriptableObject {
	public string color;
 
	void Awake(){
		color = "red";
	}
}

using UnityEngine;
using System.Collections;
 
public class main : MonoBehaviour {
	void Start(){
		Car polo = (Car) ScriptableObject.CreateInstance(typeof(Car));
	}
}