I select a row of polygons which lay along the seam , and extrude them slightly to get a raised seam.

You can do seams with a bump or displacement map too.

Conforming clothing does not have to be a continuous mesh , so you can model the collar as a seperate piece and simply overlap it slightly with the neck opening.

• sorry I use Lightwave - no idea what wing3d has as commands

another way is too select the edge along the neck opening and do an extend and move to create a new row of polygons. Then continue doing that to the top edge to build up the collar.