heavy scene loading

hello there…i have problem with my environment scene which is the scene a bit heavy when i want to load form mainmenu…how to overcome delay of the scene??i have idea like at the main menu after we enter the button level to environment put up the loading effect to make sure the environment load first before start…we can do it like that or not???if can can u show me how to do??

Note: this is a Unity Pro feature,

Here is a code snippet,

public class LoadLevelAsynch : MonoBehaviour 
{
    AsyncOperation ao;

     public void LoadLevel(string LevelID)
     {
        ao = Application.LoadLevelAsync(LevelID);
     }

  
    void Update()
    {
        if (ao != null)
        {
            Debug.Log("LOADING....." + ao.progress);
        }

    }
}