You may create your Character for use in popular 3D software like Maya® and 3DSMax®. You specify your preferred output formats, skeleton type, polygonal resolution, others, and you can even add a custom set of 77 blendshapes to drive facial animation.This service can give those experimenting with Second Life's new mesh capabilities a head start for imports into the modeling platform of their choice. Avatars for a number of other platforms including Project Wonderland and realXtend can be exported directly to the host format.
Here's a brief walk-through I created a couple of years ago. The features illustrated are still the same.