3D Studio Max
Insert the edges vertically.
Lastly, select the 2 vertecies in red and weld them into one.
Insert with Cut the edges all around the neck.
For that select a face and with shif+Move make an Element copy.
Position there on the chest just away from the body.
Adjust in the user view the vertexes to have a harmonious curve as shown.
The final result depends entirely on the care which you take to build this foundation, therefore try to spend some time here.