Been working on my paint chops recently and I am finding Portrait Painting Atelier by Suzanne Brooker quite informative. Chapter Five: The Painting Process is particularly useful, in 14 pages laying out a way of systematizing the approach. The breakthrough for me was in the section ‘Working in grisaille’* because I never fully understood the relation of the underpainting to the finished piece.
Also under ‘Handling the brush’ I found “Brushwork is the signature of a painter. Every brushstroke interprets light, volume, space, movement, direction, or texture. This means that your intention must be clear before the brush touches the canvas.” So true in anything, the intention is what will pull it off.
**Grisaille (French: gris ‘grey’) is a term for painting executed in monochrome or near-monochrome, usually in shades of grey. Many grisailles in fact include a slightly wider colour range. Paintings executed in brown are sometimes referred to as brunaille, and paintings executed in green are sometimes called verdaille. A grisaille may be executed for its own sake, as underpainting for an oil painting (in preparation for glazing layers of colour over it), or as a model for an engraver to work from.