You can use Sysinternals psexec to setup powershell remoting … remotely.

Get psexec.exe from here: https://technet.microsoft.com/en-gb/sysinternals/bb897553 

The command to install it is:

psexec \%PCNAME% -h c:windowssystem32winrm.cmd quickconfig –quiet

Where %PCNAME% is the name of the PC you wish to install it on.