Here at the Delhi Asylum, we've used the RealSense 3D scanner for scanning everything from objects to people. That particular scanner generates fairly high resolution scan data, which can both be a blessing and a curse, because while it retains details, it makes it fairly difficult to work with in terms of poly counts.
Like Anool mentioned, you could use a Kinect to scan your subject. It works fine, but the Kinect provides much less detail, and features can often get mixed up.
The scanned data then needs to be cleaned up in an application like Autodesk Meshmixer. Depending on the extent of post production needed or desired, you could also polish up the geometry in a digital sculpting application like Zbrush or Mudbox.
We print them at a resolution of 0.2mm, which gives us good results with full body prints, or 0.1mm if it's a bust to ensure adequate detail around facial features, etc.
The prints are then given an acetone bath, this ensures the ridges (which happen due to the layering of filament in FDM) are made smooth. This is of course an optional step.
The busts are then manually painted. We have a couple of artists here talented at sculptural painting. They paint over the prints with acrylic paints, and that's how we do those busts.
Here's a few of those busts we've printed here.