How to assign a public IP to VM

hi guys, im trying to assign public IP to my VM in windwos azure but i can to see be geting this instructions correct somehow

im following these instructions

http://blogs.technet.com/b/canitpro/archive/2014/10/28/step-by-step-assign-a-public-ip-to-a-vm-in-azure.aspx

Im getting stuck at

Get-AzureVM -ServiceName pr-net1 -Name vnet1-app-1 | Set-AzurePublicIP -PublicIPName Appip | Update-AzureVM

where i enter my VM name at  -Name it gives me the following error

"Get-AzureVM : A parameter cannot be found that matches parameter name 'myvm'."

Of which the VM name or there is other VM name im suppose to look at please advise THANKS