Oil paints are extremely versatile. They can be used thickly in impasto or thinly in glazes. (Impasto is a technique used in painting where paint is laid on an area of the surface (or the entire canvas) very thickly, usually thickly enough that the brush or painting-knife strokes are visible. Paint can also be mixed right on the canvas. When dry, impasto provides texture, the paint coming out of the canvas).

Oils can also be opaque or transparent.

The proportion of oil paint should be increased for each subsequent layer in an oil painting - this is known as painting 'fat over lean’. The lower layer absorbs oil from the layers on top of them. If the upper layers dry faster than the lower ones, they might crack.

Avoid using ivory black in under paintings as it dries much slower than other oil paints.

Pigments containing lead, cobalt and manganese accelerate drying. They can be mixed with other colours to speed up drying and are ideal for under layers.

Avoid using linseed oil as a medium in whites and blues as it tends to dry with a yellow hue. Poppy oil has the least tendency to dry yellow but dries more slowly.

If, as the paint on your palette dries it forms a lot of wrinkles, too much oil has been added.

If you are not sure whether a bottle of mineral or white spirits is suitable for oil painting, put a tiny quantity on a piece of paper and let it evaporate. If it evaporates without leaving any residue, stain or smell, then is should be okay.

If you want to clean away a layer of oil paint or varnish, use alcohol, which is a powerful solvent.

To stop dust getting onto a still-wet oil painting, face it towards a wall so that dust will have less tendency to stick on it.