To paint with a loaded brush I mix a series of colors of similar values. If I'm painting a sky I mix up at least three patches of color that when combined are very similar, but not identical, in value to the sky I am painting. I mix a blue that is a little bit yellowish (white, thalo blue, and cadmium yellow light). I mix a blue that is a bit reddish (Cadmium red, indanthrone blue, and white) and a blue of equal value as the other mixtures (titanium White with indanthrone blue). If I want the sky to really shimmer I might mix up two blues. One warm, like a thalo blue, and a cool blue like indanthrone, again, both of similar value.
I then take these three or four colors and swipe them with the palette knife (using my left hand). I then apply this mixed pigment to a large flat bristle brush I hold in my right hand. I very carefully and slowly apply this paint to the canvas. With a bit of practice you will be able to quickly pick up paint from your palette, mix it with the palette knife in your left hand, apply it to your brush, and then apply it to the canvas.
I demonstrate this technique not because I insist it is superior but to demonstrate a very controlled method of getting a variety of paint on the brush. It may seem complicated but if you rely on swiping your brush through a messy palette to get variegated color you will probably be disappointed. It isn't necessary to paint every stroke using such a controlled method but it is extremely useful in painting areas that need energy and vibration like foliage, skies, roads, or any main point of interest.
Another way to get multi-hued strokes is to make little piles of paint very close to each other on the palette. You then swipe this pile of paint with the brush being careful not to over mix the paint, then very carefully apply this mixture to the canvas. This has the advantage of being much faster.
The most common method (and least satisfying for me) is to use the brush to pick out bits of color from piles of paint from the palette being careful not to over mix as you pull paint onto the brush. This method is a little harder to control because I tend to get lazy and start using paint right out of the tube. I find it is much easier to get things right if I very carefully mix the colors I want to commingle.
No doubt other methods, or combinations of methods, are possible. Let me know your favorite technique.
Brad Teare © 2009