When sculpting a head, how do you fit it for a neck?

I'm thinking of sculpting a head, but I don't know how to sculpt the neck and make it so that it can be attached properly to a body. Any tips?

you can sculpt one without a neck and make hole to fit a necked body, other than that, sculpt a solid neck on the head and drill/dremell a hole to fit a neck adapter

take a measurement of neck and use a wooden dowel wrapped in foil or saran wrap for necked heads. for sculpted necked bodies. i suggest buying a few heads and studying them to see how deep it should be and measure neck ball for getting the proper dimensions for hole. reason being is every company does their heads slightly different for the necked bodies. so a head from each can help you gauge them better.
Hot toys is semi universal. muscle bodies need bigger heads for the wider neck base.
i suggest buying a kumick head or dc direct there neck base is buildt big for these bodies. and you can see how mig or small you need. then use a wooden down the adding miliput to keep it still.