You can apply for Canadian citizenship again. This new application must include all the required forms and documents, including a new application fee. There is no waiting period before you can reapply. However, you should make sure you meet the requirements for Canadian citizenship before you reapply.
If your citizenship application is refused, you may also seek judicial review of the decision by the Federal Court of Canada. This is not an appeal of the decision. You have thirty (30) days from the date on the refusal letter to apply.