To enable Winrm

Check that the service is running

PS C:\powershell> get-service winrm
Status  Name        DisplayName
------  ----        -----------
Running winrm       Windows Remote Management (WS-Manag...

if is is not running start it and set to automatic

PS C:\powershell> (get-service winrm).start()
PS C:\powershell> set-service winrm -startuptype "Automatic"

Do quick config on winrm

PS C:\powershell> winrm quickconfig
WinRM service is already running on this machine.
WSManFault
  Message
    ProviderFault
      WSManFault
        Message = WinRM firewall exception will not work since one of the network connection types on this machine is set to Public. Change the network connection type to either Domain or Private and try again.
Error number: -2144108183 0x80338169
WinRM firewall exception will not work since one of the network connection types on this machine is set to Public. Change the network connection type to either Domain or Private and try again.

If you have virtual machine software on your computer you will get the previous error -- then run the following code to set the adapters.

$nlm = [Activator]::CreateInstance([Type]::GetTypeFromCLSID([Guid]"{DCB00C01-570F-4A9B-8D69-199FDBA5723B}"))
$nlm.getnetworkconnections() | foreach { if ($_.getnetwork().getcategory() -eq 0) { $_.getnetwork().setcategory(1) } }
PS C:\powershell> winrm quickconfig
WinRM service is already running on this machine.
WinRM is not set up to allow remote access to this machine for management.
The following changes must be made:

Create a WinRM listener on HTTP://* to accept WS-Man requests to any IP on this machine.
Enable the WinRM firewall exception.
Configure LocalAccountTokenFilterPolicy to grant administrative rights remotely to local users.
<
Make these changes [y/n]? y

WinRM has been updated for remote management.

Created a WinRM listener on HTTP://* to accept WS-Man requests to any IP on this machine.
WinRM firewall exception enabled.
Configured LocalAccountTokenFilterPolicy to grant administrative rights remotely to local users.

To add computers to the trusted hosts:

PS C:\powershell> winrm s winrm/config/client '@{TrustedHosts="10.21.1.3"}'
Client
  NetworkDelayms = 5000
  URLPrefix = wsman
  AllowUnencrypted = false<
  Auth
    Basic = true
    Digest = true
    Kerberos = true
    Negotiate = true
    Certificate = true
    CredSSP = false
  DefaultPorts
    HTTP = 5985
    HTTPS = 5986

TrustedHosts = 10.21.1.3