Painting Like The Masters:

Oil paintings began in the Mediterranean during the era of the Greek and Roman civilizations. The Egyptians also used paint techniques that were rich in bees wax, pigments of such minerals as copper, iron and manganese oxides and tempera.
While historians have noted that the Mediterranean civilizations of this time were aware of flax, walnut, poppy seed and other vegetable oils there is not definite proof that they were used in oil paintings of the time.
The tempera these early oil painters used were organic mediums mixed as fluid with water and volatile oil additives. Italian artists of the next century used organic binding ingredients such as materials containing protein from whole eggs, animal glue or milk.
From the Roman Empire's demise to the 15th century Renaissance era oil paintings and tempera painting became prevalent. In Greece and Italy olive oil was the preferred based for pigment mixture preparation although this made for a long drying period and great difficulty for human models. Theophilus, a German-born monk and oil painter in the 1100's dispensed with olive oil in his oil paintings. In Japan a substitute for oil paintings was perilla oil, applied after a lead application as early as the 8th century. During the 1300's the Italian Cennino Cennini created oil paintings that were a combination of tempera and several layers of light oil.
Much later Leonardo DaVinci, who lived until 1519, created his own oil paintings concoction made by adding up to 10 percent bees wax to his oils and then boiling the combination.
If you'd like to follow in the footsteps of these great painters there are some simple preparations and techniques before and during your creation of oil paintings.
The first important technique is to dress for it, including gloves. Your tools include two containers, one with paint thinner, and the other with a combination of two parts thinner to one part walnut oil. Make sure you've made room in easy reach for your paint brushes, your palette and its knife, your containers, paint tubes and paint rags.
Your palette should start out with only 2-3 paint colors. Generally you'll need cadmium red, cadmium yellow and ultramarine blue to start.
Your palette knife is the oil paintings tool you use for the technique of mixing colors. Keep in mind that oil paints have a short blend life, so if you try to make a color change and it doesn't work right the first time quickly take a paint rag and wipe it off the canvas and start over.
One of the advantages of oil paintings that make the correction technique so much easier is that they take nearly a full day to dry. So, you have lots of correction time. On the other hand, because oil paintings take so long to dry and excessively heavy coat can slow your painting process considerably.
The brushes you use in your oil paintings must be cleaned well between each change of color. This technique is crucial. The first thing you do is remove as much of the paint as you can with the paint rag and then place the brush in the paint thinner. Swish the paint brush around in the thinner, and then dry it with the rag.
You must wait 24 hours after your first complete oil paintings application before you start your second or the first application will smear.