Decide if you want to use tempera powder or pre-mixed tempera. Each has its own advantages and drawbacks. You will need to prepare tempera powder by mixing it in water, but it is easy to control the thickness. Pre-mixed tempera can be used without going through the preparation phase, but controlling its thickness is more difficult.
To paint more effectively, be sure to choose the correct painting paper or surface. It is easier to paint with tempera on paper that has a water base, for instance watercolour paper. Consider painting with tempera on surfaces such as wood or canvas.
Be sure to get the thickness right, depending on the type of painting. If you want to make the painting look transparent or resemble a glass painting, use thin tempera paint. For more opaque paintings, you will need to use thick tempera paint.
An important fact that you will need to remember while painting with tempera is that it dries very quickly. For this reason, you will want to paint in short swift brush strokes. To build up depth in your painting, use multiple paint layers.
Blend together multiple tempera colours to make any desired shade. Take the help of a colour wheel to determine which primary colour you will have to mix in order to make a secondary colour: green can be made by mixing blue and yellow; purple can be made by mixing blue and red.
Be sure to allow enough time for the tempera to dry completely. Although tempera feels dry to the touch quickly, you might have to wait for a long time before the paint cures completely. It may sound surprising but paintings with a large number of layers may take about a year to dry completely.