Egg tempera paint is simply made from artist quality finely ground dry pigments, egg yolk and water.
In the first instance, the egg medium should be obtained. The standard medium is pure yolk which is free from the white.
If white is included in the medium it will cause the paint to dry more rapidly and to drag on application.

Obtaining the egg medium

Having cracked open an egg allow as much of the white to drain off then continue the separation either by means of an egg separator or by transfering the yolk from the palm of one hand to the other.
Transfer the yolk to a paper towel and gently roll the yolk towards the edge of the towel.

Pierce the yolk sac and allow to drain into a clean container.

Then add about a teaspoon of water and give it a good stir. You now have the medium which will bind the pigment particles.

Once the sac has been pierced the contents will start to set up. It is therefore adviseable to use a fresh egg each day.
The yellow of the yolk may initially effect the colors, however, the yellow will bleach out within a day.

Most tempera painters prepare their pigments into a paste form.
Water is added to the dry pigments to form a stiffish paste.
Some pigments are gritty and it is adviseable to grind these pigments further.

 
Initial mixing of dry pigment and water with a palette knife.

 
Grinding with a muller and plate.

Making the Paint

 
Place a small amount of the pigment paste onto the palette.

Add about equal volume of the egg medium and mix well making sure there are no lumps of pigment. Some pigments require slightly more egg medium, some require less.

Add water, trial and error will dictate just how much water is required. Any amount of water can be added, the important ratio is the pigment paste to egg medium.

Once the paint has been made it cannot be stored so only make sufficient paint for the particular painting session.
Tempera paint is insoluable to the extent of not being picked up by over painting and when completely dry is relatively water resistant. However, the paint is not absolutely water proof and can be disturbed by the application of water.