The paper used for watercolor painting is a specialty heavy paper at least 90lb. (To give you an idea of the thickness, standard card stock is 60 or 80lb.) Heavier, thicker, paper, such as 140lb, will buckle less from the moisture used during the painting process.

Layering is a technique used in watercolor as well as in other types of paintings. A wash has to completely dry before more can be done such as adding details on top. Or a glaze may be put over a wash.

Watercolor painting has its own challenges. If you look at watercolor paper, you’ll see it is very thick so it can stand the amounts of water used without warping (at least warping too much).

Pastels are powdered pigment and a binder in stick form. There are soft, hard, pencil, oil and water-soluble pastels.

Soft pastels can be readily smudged and blended, which is great while working on a piece, but means they need a fixative afterwards.

Varnish is used on top of oil or acrylic paintings, in the former case to help prevent the oils yellowing, and in both cases to a different sheen (matte or glossy) to the finished painting. Varnish on a painting that will not be under glass also protects it from damage by dirt, dust, and pollution.

Putting varnish on a painting is not something that can be rushed. The paint must be completely dry. For an oil painting that can take several to six months depending on the paint.