Watercolor is made either in tubes or pans. In the tubes the color is very soft and pliable. In the pans it is a little harder and must be worked up with the brush to make a wash. Because of the addition of either sugar or honey or glycerine, the colors in the pans should be moist.
If the color in the pan becomes too hard it will be more difficult to dilute with water. This often happens if you have a large selection of colors that you don't use often. If you narrow down your range, you will use them all and there won't be any waste. It is really much better to buy your tubes or pans of color separately as you require them instead of buying a complete set in a box when you are invariably sold more colors than you will ever need. As tin boxes for holding colors and for use as a palette can be bought empty, this problem is easily overcome.
Generally speaking, you only need a watercolor box for outdoor painting. In the studio a few tubes and a large white plate, for use as a palette, are quite enough. Jam jars make excellent water pots and a table on which to prop your drawing board is all you need (Fig. 15).
For working outdoors, a tin box is useful, doing the office of palette and container. For a water pot any small sized plastic bottle is ideal.
The range of color to choose from, both in oil and watercolor, is vast; therefore start with the simple primaries; red, yellow and blue, as your first choice. Cadmium pale yellow, cadmium red and Monastral blue are good primaries; add ultramarine, burnt or raw umber and you have a good palette to begin with. When you have experimented with them, other colors may be added to your palette as required.
With the six colors I mentioned above you should be able to mix most tints to enable you to understand the nature of mixing color. The rules for mixing tints in watercolor also apply to the opaque colors and to oil.
Tubes are easier to handle indoors than pans; outdoors pans are probably the most convenient except for yellow which is inclined to get dirty.