This is a very simple code snippet which we need most of the time. I thought it will be handy to publish this PowerShell command for any one who might look for a way to create State Service Application on SharePoint 2013
New-SPStateServiceDatabase -Name Farm_StateService_ContentDB | New-SPStateServiceApplication -Name "State Service Application" | New-SPStateServiceApplicationProxy -Name "Farm State Service Application Proxy" -DefaultProxyGroup
Cheers
