In Phaser, how should I be managing state? [closed]

Question

I'm quite new to Phaser and JavaScript really confused about state management.

Phaser has lots of documentation and info on the net, but everyone seems to be doing it a different way.

An example:

var game = new Phaser.Game(800,600, Phaser.AUTO, 'phaser-demo',
        {preload: preload, create: create, update: update, render: render});

function preload(){ ... }
function create() { ... }
function update() { ... }
function render() { ... }

Another:

window.game = new Phaser.Game(800, 600, Phaser.AUTO);
// all other states are in different files

module.exports = {
    preload: function(){ ... },
    create:  function(){ ... },
    update:  function(){ ... }
};

I would be grateful for a simple overview of properly handling states.