saving high score and displaying it

i know there are lots of questions on this but i dont know how to apply it to my code

using UnityEngine; using System.Collections;

public class FlyPickup : MonoBehaviour{

 private GameObject pickupPrefab;
 void OnTriggerEnter(Collider other)
     // if the "Collider" other is tagged with "Player"...
     if (other.CompareTag("Player"))
         //...add the pickup particals
         Instantiate(pickupPrefab, transform.position, Quaternion.identity);
         //...Decrement the total number of flies..
         //... update the score


Try storing the score on a variable using PlayerPrefs then just compare the value to the current score. If the current score is higher than the value stored in PlayerPrefs, store the current score to the PlayerPrefs