This ain't a tutorial, just a little thought of mine that might help the one or the other - i mostly paint my sockets black because it is neutral and gives a good view to the model. Most of the time i do paint my miniatures (small scales, busts, big scales, etc.) on a fixed display or gaming base.
After bringing up the first colours on the models there comes a moment where i take some black colour to paint the socket black. The model is not finished yet and might be still in early process but it helps my eye to get a good focus at the model when the bright wood colour disappears. It helps me to see how it will look in the end, it helps me to get a clearer view. I am really doing this in the beginning after the first colours. By holding it in my hand there will be some damage on the black that i have painted earlier but i just clean this up with another layer after the model is finished.
I also got an example on how the black socket or base edge helps me focus to the important area on the model. Here you can see some of my actual Work in Progress again and taking a closer look on both the Roman Matrona busts shows that a black socket helps the eye more than a bright socket, the bright one somehow distracts from the model itself - at least it works for me:
I have no idea if this might be of interest for you, but i hope so... it really helps my eyes to concentrate - am i getting old?
Keep on happy painting!