This is a simple guide to the basics of subsurface scattering. There's probably a lot more to it, but this is most of what you'll need to know as an artist (imo). The best advice I can give on the subject is to try and learn it because there aren't any explicit generally applicable directions on how to achieve this look (that I'm aware of); the effects of SSS are highly variant and contingent on a number of factors including (but not limited to) light intensity, light color, light directionality, light quality, material, specularity, composition, density, texture, context etc etc etc.