When John Singer Sargent traveled to America in 1890, he went painting with Frederick S. Pratt, an amateur painter and founding trustee of the Worcester Art Museum.
Luckily for us, Pratt wrote down what Sargent had to say about painting methods.
“Choose simple subjects, near objects at first. Do not try to make a pretty picture so much as to render truthful effects. Paint over the whole canvas with colors approximating the masses so as to obscure [sic--did he mean establish?] relations of tones while working—when finishing, ‘paint into paint’ when possible and in portraits, paint around the features in detail, using small brushes rarely.
“Always use a full brush and a larger one than necessary. Paint with long sweeps, avoiding spots and dots (‘little dabs’). Never think of other painter’s pictures or how some one else would treat a subject but follow your own choice of colors with exact fidelity to nature.”
Quoted in the new book: John Singer Sargent: Figures and Landscapes.