To upload file from ckeditor you just have to use following four step and that's done.
Include Ckeditor library file
<?php echo $this->Html->script('/js/ckeditor/ckeditor');?>
Textarea with class ckeditor
<?php echo $this->Form->textarea('StaticPage.page_content',array('class'=>'ckeditor'));?>
<script type="text/javascript">
CKEDITOR.replace( 'data[StaticPage][page_content]',
...
