Tips for beginners: Techniques

I want to dispel the myth that painting in oils is particularly difficult - it isn't! But there are one or two simple rules to follow to ensure that your painting stands the test of time.

RULE NO. 1: If you dilute your paint with spirits, make sure you add a drop or two of oil as well. I explain fully about spirits and oil mediums on my Oil Painting Materials page and why this is important. This section will also tell you why it's important to buy a pre-primed surface, otherwise you will need to 'size' and prime it yourself.

The 'fat over lean' rule simply tells you that it's not a good idea to make your first layer or two very thick, and then put thinner paint above it. This is because as the paint below dries more slowly and contracts it can cause the paint above to crack. So make sure that your first layer is quite a thin one. You could rephrase this rule: 'more flexible over less flexible' - so make sure that you add a drop or two extra oil to subsequent, thicker layers to give them added ability to flex rather than crack.
(Above, a thick 'impasto' top layer by Van Gogh, applied with a palette knife)

Now of course, you may not want to work in lots of layers. You might want to work with only one. However it's more likely that you'll want to apply your paint in a few layers, letting each one get dry to the touch before you come back to the painting and add more paint. With only one layer, you'd probably find the original white colour of the pre-primed canvas showing through in a way you might not like.

As I mentioned, a pre-primed canvas will be brilliant white in colour, so you may want to begin your painting by either blocking in large areas of colour (see an example of this method for making a painted portrait by clicking the link), or by applying a base layer of one particular colour to the whole canvas. One major advantage of this is that when faced with a bright, white canvas, you may find it hard to judge the tones you want to put down - whereas if you start off with a canvas that's painting in a mid-tone (say a brown, or bluey-grey) these tones become easier to discern. This is particularly the case if you are painting from 'observation'.

So - if you want to apply a base layer then follow the 'fat over lean' rule above and apply a reasonably thin layer of paint, using a stiff dry-ish brush to spread it well over the canvas. Another reason for applying a first layer thinly is that you don't want to have 'ridges' in the paint when you come to begin your painting. If this happens, you can sand any ridges down with some fine-grade sandpaper once it's dry. Finally, it might be worth adding a drop or two of 'drying oil' to your first layer. You'll find that the first layer of paint takes the longest time to dry, and each subsequent layer will dry more and more quickly. This is because when applying later layers the oil in them will sink down and be absorbed by layers below.

A NOTE ABOUT WHITE PAINT FOR YOUR UNDERLAYER.
The standard white paint used to be Lead White, also known as Flake White. Unfortunately, this is toxic! Now we choose between Titanium White and Zinc White. Titanium White is a nice, opaque white, but is slow to dry, so you may not want to use too much of it in your first layer. Zinc White dries a lot faster, but can cause cracking so do not use a lot of it in your underlayer. Windsor & Newton and Daler-Rowney both make an 'Underpainting White' colour which is a mix of Titanium and Zinc, with added texture to help the later layers of paint adhere. It has a faster drying time than using Titanium alone.

Of course thicker coats of paint will dry much more slowly than thinner ones (whether they are thinner because you've spread the paint more thinly, or because you've mixed it with a spirit or oil to dilute it) However you'll also notice that different colours take varying amounts of time to dry. Lighter colours seem to me to take much longer than colours with darker pigments in them. This is another reason to apply a mid-tone, sightly darker first layer. Be aware that Titanium White takes a long time to dry. I use Titanium for upper layers, but for a first layer I will use Zinc White - which dries a lot faster - and will include some drops of drying oil. You can  find information on my Oil Painting Materials page about drying oils.

I like to group my colours together on my palette (reds and yellows, greens, blues, and browns) and to keep these groups in the same places on my palette each time. This sounds a little militarian, but you'll find that if you do this you'll soon learn by instinct which part of your palette to look for the colour that you want and won't have to search each time. At the end of a painting session, if you want to keep the colours you have squeezed out or mixed up then cover them with Clingfilm (Saran Wrap) - as long as the air can't get to them they won't start to dry out.