My setup (before going outside):
Related websites:
http://www.demilked.com/macro-snowflakes-diy-camera-alexey-kljatov
http://digital-photography-school.com/how-to-focus-stack-macro-images-using-photoshop
http://psoup.math.wisc.edu/papers/h3l.pdf
http://chaoticmind75.blogspot.ru/2013/08/my-technique-for-snowflakes-shooting.html