How to name a private method in a language which doesn't support privacy?

Question

What's the coding standard for naming a private method in a language which does not have the private modifier? Specifically, I am talking about Javascript. Below I've placed an underscore at the end of my private method's name, but a colleague told me that underscore is usually for class fields.

var MyClass = Class.create({
    initialize: function() {
        alert('constructor');
    },
    publicMethod: function() {
        alert('i am public');
    },
    privateMethod_: function() {
        alert('i am private');
    }
});

Answer 1

As everyone told you in a comments, most people(and some languages) use single underscore.

Answer 2

EDIT: Per the comment below by @Raynor, the approach below is not a good way to achieve privacy in JavaScript. See: http://blog.jcoglan.com/2012/01/19/the-cost-of-privacy/

---

I use this convention:

var MyObject = (function() {
  var initFunction = function() { /* init some stuff */ };
  var privateFunction = function() { /* state secrets */ };

  return {
    init: initFunction
  };
})();

Only the public functions are returned. As you may guess I also tend to use only methods when using this style, no public properties.