Select a set of cake or moist pan watercolours if you prefer them. Most have a good selection of basic colours you’ll need for transparent watercolour painting. Do not use the white paint that is included in most cake or tube colour sets. It’s opaque. Its use would change your watercolour paintings into gouache paintings. Gouache or opaque watercolour is a distinctly different category and approach to painting.
If you prefer tubes pre-packaged tube sets will also give you a good starter selection of colours for watercolour painting. Start by using brand name “highest quality student” grade watercolours until you can commit your resources to buying “artist” grade watercolour supplies. If you are already confident with watercolours, buy the best quality you can afford.
If you can afford only one brush, buy a #4 round red sable watercolour brush. Otherwise buy the best synthetic or synthetic-blend brush Most manufacturers have starter sets that contain very usable equivalents.
Starter Colours: Ultramarine, Cerulean Blue Hue, Cadmium Red Hue, Alizarin Crimson, Cadmium Yellow Pale Hue, Lemon yellow.
These six colours, Warm Blue / Cold Blue, Warm Red / Cold Red & Warm Yellow / Cold Yellow, enable the mixing of a wide range of colours.
Useful additional colours are:
Light Red, Raw Sienna, Burnt Sienna, Burnt Umber, Payne’s Gray, Cobalt blue, Winsor blue, New Gamboge Hue.
Ready made greens are not as a wide range of greens can be mixed from the colours above
Use any watercolour pad, block, or loose paper with 300gsm. The heavier the paper, the less likely you’ll have to deal with the paper warping while you are painting.
For tube watercolours you can use a flat white dinner plate or buy some inexpensive 6 or more welled plastic palettes.
Find a glass, or jar, to hold fresh, clean water. Use two if possible. One for rinsing your brush between colours, and one for clean water for painting.
A few more odds’n’ends will round out your kit. A pencil, a kneaded eraser, some tissues, and an old towel or paper towels, a small natural sponge.
For finished art samples that you will be sending to publishers you will need to upgrade your paints to artist-grade and your paper to archival quality.