Dear Shine.chandu,
I recommend you writing the draft of the notice on your own and uploading it here. Some senior like me will correct it. In the notice, write clearly what would be process for the approval for leave, salary advance etc.
In most of the companies, all type of applications are first approved by the respective HOD of the employee. Later employee submits it to the HR Department. HR, in turns submits it to the approving authority and later communicates the decision of the approving authority.
Nevertheless, we need to look at the other side too. Following the hierarchy is important to the MD as much to the employees. Your MD also should note that bypassing HODs, he too does not deal with the juniors directly. Otherwise your notice will become hollow very soon!
Thanks,
Dinesh Divekar