For editing user information in cake php by clicking on edit button we have to first pass user id in URL by using below code in our view.

<?php echo $this->Html->link('Edit',array('action'=>'edit/'.$user['User']['id'])); 
		         

And we have to put the following code in that function where we will wright code for editing data in our controller.

 public function edit($id = null){
         
       
        $user = $this->User->findById($id); //getting user information on the bases of id which we are passing
        
       if ($this->request->is('post')) {

          
            if ($this->User->save($this->request->data)) {
                $this->Session->setFlash(__('The user has been updated'));
                $this->redirect(array('action' => 'display', $id));
              }
               
            else{
                $this->Session->setFlash(__('Unable to update your user.'));
            }
        }

        if (!$this->request->data) {
            $this->request->data = $user;
        }
    }