<input type="file" name="data[FileUpload][file]" id="myFileToUpload">
<a id="pickFile" href="#">Upload&nbsp;Now</a>
<script type="text/javascript">
    $('#pickFile').click(function(e){
    	e.preventDefault();
    	 $.post(
    			"/admin/FileUploads/saveFromFlash/<?php e($session->id()) ?>",
    			{ data:$("#myFileToUpload").val() },
    			function(data){
    				$("#returnedContentFromAjax").html(JSON.stringify(data));
    			},
    			"json"
    		);
    });

</script>

$this->FileUpload->save($this->data)

if (!isset($this->data['FileUpload']['file'])) {
        $this->setUploadError('No upload passed');
    return false;
}

{ data:$("#myFileToUpload").val() },