In your login page you have two fields that are username/email and password in that page you have a checkbox . In that form you have a checkbox if you select that check box then your cookies will be saved in your browser for that remember me code you have to save select that checkbox for that you have to write few lines of code.

Code for Appcontroller goes here:

	public function beforeFilter() {
        // parent::beforeFilter();
           $this->Cookie->key = 'qSI232qs*&sXOw!adre@34SAv!@*(XSL#$%)asGb$@11~_+!@#HKis~#^';
    $this->Cookie->httpOnly = true;

    if (!$this->Auth->user() && $this->Cookie->read('done')) {
        $cookie = $this->Cookie->read('done');
        // echo debug($cookie);

        $user = $this->User->find('first', array(
            'conditions' => array(
                'User.email' => $cookie['email'],
                'User.password' => $cookie['password']
            )
        ));

       
    }

you should also write this code also in your AppController:

public $components = array(        
		'Qimage',)

 Code for the UserController goes here:

This is the login function in UserController

public function login() {

	 if ($this->Auth->user())
			    {
			        $this->redirect(array('controller'=>'users', 'action'=>'home'));
			    }

    if ($this->request->is('post')) {

        if ($this->Auth->login()) {

            // did they select the remember me checkbox?
            if ($this->request->data['User']['done'] == 1) {
                // remove "remember me checkbox"
                unset($this->request->data['User']['done']);

                // // hash the user's password
                // $this->request->data['User']['password'] = $this->Auth->password($this->request->data['User']['password']);

                // write the cookie
                $this->Cookie->write('done', $this->request->data['User'], true, '2 weeks');
            }

            return $this->redirect($this->Auth->redirect());

        } else {
            $this->Session->setFlash(__('Username or password is incorrect.'));
        }
    }

    $this->set(array(
        'title_for_layout' => 'Login'
    ));
   $user = $this->Cookie->read('done');
    $this->set('user', $user);
    $this->set('check', 1);
}

This is the logout function in UserController:

   public function logout() {

     	  $this->Cookie->delete('remember_me_cookie');
              
                return $this->redirect($this->Auth->logout());
            }

   

Code for the checkbox goes here:

 <?php echo $this->Form->checkbox('done' ,array('hiddenField' => true,'checked'=>$check));?>