Auto scaling of VM with IIS and Custom service deployed

Hi

We have one   2  VM's with IIS ,We deployed rest service on the both VM's .Setup load balacner to redirect traffic to these VM's.

Untill this  everything working fine.  Recently business has increased and asking to scale up on few business days and holidays season.

i come across one nice feature available on Azure where we can setup auto scale of VM based on certain condition.

But i dont know how can i Deploy my Rest service on the newly automatically On demand based created VM's.

Please suggest how can i do that.