How to create only once my static list when create my object again and again

How to create only once my static list when create my object again and again

I have an class and one of the class members is static list that keep all
my object and i only want to create this list (List<myObject> list = new
...) once. what is the best way to do it ?
public class MyObject
{
private string _name;
private static List<Capture> _list;
public MyObject(string name)
{
_name = name;
}
public void start()
{
_list.Add(this);
}
}