For using a wcf service in wpf application Should we create wcf service as a project if as a project then WcfService library or wcfservice application or as a website And how we use service reference or call classes in service reference from wpf

For using a wcf service in wpf application

Should we create wcf service

as a project if as a project then  WcfService library or wcfservice application

or

as a website

And how we use service reference or call classes in service reference from wpf project