protected function prepareData()
    {
        if (!empty($this->data)) {
            if ($this->method === HttpMethods::GET) {
                $this->url = Utils::appendUrlQuery($this->url, $this->data);
            } else if ($this->method === HttpMethods::POST) {
                curl_setopt($this->curl, CURLOPT_POSTFIELDS, $this->data);
            }
        }
    }