@StardustLarva: Thanks! I don´t really like the rendering here :)
@maggie: Thanks very much. Drop by any time.
Here is an example study sheet of how I do studies these days. Both are portrait studies and I do living and dead master studies (I don´t post them all here as these usually are boring and not very pretty and I also don´t want to post too many studies from living masters purely for copyright reasons). The first is Bouguereau and the second study is from a character by Marko Djurdjevic, here is his dA page:
http://marko-djurdjevic.deviantart.com/
What I do here is not making a 1:1 copy, I analyze the painting and try to focus on what is important for me and what I want to learn. Here I focussed on values, lighting and what colors where used and how were they used.
I first guess all the b&w values from the colored image, then I guess the colors and finally compare the real ones to my guessed, noting where I was off.. Then I do a quick study painting where I don´t go for accuracy but for use of colors, values, trying to memorize everything. I also make notes for future reference.
After that I could go back and do an accurate painting of the studied image, if I desire or think it will help to increase my knowledge on the subjects.
The second image is an application from mind some time after the studies.