The technique of beginning a painting by blending white into the background can pose many problems, however if done correctly, it can produce beautiful effects.
Golden Acrylic Paint Manufacture doesn’t create mixing white. So, if you are a Golden fan, there has to be away around this…. Ah, yes, use some gesso and water, with a touch of glazing medium. This will blend without lightening the colors too much. Much of the time, you are just blending distant trees for landscapes with this technique.
In order to do this technique without complaint, spray the canvas with an atomizer, and load your brush with gesso and a bit of acrylic glazing medium and crisscross the brush across the top of the canvas, gradually getting less and less toward the end of the canvas.
It should stay wet for at least a half hour in more moist areas, like Oregon, and about 15 minutes in dry areas like Southern California.

First spray the palette with some water, then lay down at least a nickel sized amount of paint, then mist the paint.

When blending with acrylics get the colors you want, mix them out on the palette. Put one thick line of the first color, make sure it is wet, then take the second color and do the same thing right beside the first color. Criss-cross the two colors from top to bottom. Then while they are still wet, brush the center of the two, down in a quick stroke. Ta-da, nice blended acrylic colors.