All the information given for watercolour can be equally valid when using acrylics and, of course, this type of paint can be used thickly in impasto effects using a palette knife. It can be mixed with watercolour and oil paint. It accepts textural additions to the paint very well to create surface interest. Acrylic paint is noted for its bright colour and its drying ability in contrast to oil paints when used in a similar manner. It can be effectively used in combination with other materials for thickening.
Some colours, such as yellows tend to be transparent in nature. If trying to obliterate something underneath, it may be best to put white over first. Process white, which is a block to the area below, is always a useful thing to have.
You can use Gesso to seal the canvas to prevent it soaking up the paint and smooths out the rough canvas surface. Its possible to colour it with paint. A roller will make it lie flat.
Acrylic can be used as a flat colour or in a series of glazes or washes of thin paint overlaid, as used in both watercolour and oils. Allow the paint to dry between applications.
It is often nice to paint on wood, which can be salvaged – from an old door, for instance. The wood must be cleaned and sanded. Gesso is a good thing to use first, this will seal the surface and help to prevent cracking from the wood absorbing moisture. Painting on card requires gesso to prevent the paint being soaked into the surface which can destroy it. Better not to use large pieces of card as they are difficult to keep in good condition whilst using a lot of paint on them.