I use two palettes for the majority of my work: a Winsor & Newton Cotman Field Sketch Box for my sketchbook work; and a John Pike palette for my studio work. I use Holbein transparent watercolor for both palettes.
The field sketch box comes with student grade half pans which I remove and replace with a squirt from the tube. I do not fill the Pike palette with the entire contents but rather refresh the palette before each painting session with a small amount of paint. I spray both palettes with water a few minutes before painting to make sure the paint is nice and juicy.
Here are my colors:
Permanent Alizarin Crimson
Cadmium Red Light
Permanent Yellow Orange
Cobalt turquoise Light
For the present time I no longer use Opera, or Titanium White, if I can help it, although it is shown in the above photo.
I leave out Greenish Yellow, Cobalt Turquoise Light and Mineral Violet when using the field box as it only has twelve slots.