At the studio, we use a variety of approaches in creating oil paintings. One of the main differences in oil painting methods is the distinction between direct and indirect painting. The direct approach is exactly what it sounds like, trying to get all of the variables of painting: hue, value, chroma, correct in the first go.
Usually here at CRSG, we have students make a careful drawing on their canvases initially so as to keep control of the most important aspects of realist painting: drawing and placement.
A well known (and exceedingly difficult) direct approach is all prima painting. Basically the artist attempts to get the aforementioned hue, value and chrome correct and do the drawing at the same time with their brush. Not easy.
The other time-honoured method used extensively in the 15th-19th century was indirect painting. Indirect painting involves painting in layers so as to build up a rich surface in which multiple layers of paint interact with each other. This can mean using such techniques as glazing, scumbling, appying a velatura, broken colour application etc. etc.
Here is an example of direct painting, on the left. Essentially just black and white mixed to the appropriate value/tone so as to represent the experience of light illuminating the cast. It happens that this was made without a prior drawing, so essentially an alla prima work. Direct painting, of course, can also involve the use of colour.
The example on the left is an initial stage of an indirect painting method. What we have below is called an imprimatura wipe out. This started with a drawing, then, the canvas was covered with burnt sienna oil paint (which happens to be a semi-transparent colour). Afterwards, the paint was wiped out with a rag to reveal the lights. If this painting were to proceed, then this initial layer would be painted over in various opaque, semi-opaque, and transparent passages.
If you are interested in learning more about direct and indirect painting methods, come visit the studio to find out more.