How to create a dispose() inside a simple class ?

    public class Hero  // this is a simple class
    {
       public void Initialize()
       { 
           imgHero = Bitmap.FromFile(root + "spaceshipHero1.png");
       } 

       Image imgHero;
       string root = @"D:\Programe\Info\Visual Studio 2010\Projects\Game\Shoot-em\Shoot-em\bin\Debug\";
       int Width = 80; int Height = 90;
     

       public int X = 50;
       public int Y = 50;


       public void canvas_Paint(object sender, PaintEventArgs e)
       {
           e.Graphics.DrawImage(imgHero, new Rectangle(X, Y, Width, Height));
       }
       public void Pozition(int x, int y)
       {
           X = x; Y = y;
       }
       public void Resize(int width, int height)
       {
           Width = width; Height = height;
       }
     
       public void Dispose()
       {
// what is the code here that Garbage collector will clean this object efficiently?
// ex:Hero hero = new Hero();<new object  hero.Dispose();<clean new object
       }

    }
Thank you.