Acrylic paints are not that easy to get used to ... at least that's what I found when I started with them. They dry very quickly so paint often gets wasted, they can ruin your brushes and the 'covering power' of different colours varies quite enormously. So I thought that I would post a few general tips for using acrylics .... things that I have read and tried out that worked, and other things that I have found out through trial and error!
I use every sort of brush with my paints, both synthetic and non-synthetic. This is because I don't have that many brushes that I really like. I have found that the main thing to worry about for your brushes is not to let paint, medium or varnish dry on them. Absolutely fatal ... I recently totally wrecked my only 3" brush by putting it down after varnishing and forgetting all about it. Sadly, repeated soaking and washing was to no avail.
TIP for BRUSHES
Always keep a jar of water to hand to place your brush in when you have finished with it, whether temporarily or completely. The bristles will stay undamaged until such time as you can wash the brush thoroughly in warm water and liquid detergent.
I have tried several different styles of palette with varying degrees of success. The large plastic ones with lots of small paint-wells and 3 or 4 mixing areas are really only any good for very small paintings when working with acrylics. I think that these are best kept for oils or watercolours. Similarly the small round ones with deeper wells, although capable of holding a little more colour, are not suitable when you need to mix many shades or larger amounts of paint.
TIPS for PALETTE USE
White plastic picnic plates and bowls are great for mixing up larger amounts of acrylic paint. Kitchen cling wrap can be used to seal them between sessions to help keep them workable. When finished with I soak them in hot soapy water for a few minutes and all the dried-on paint films can then be washed off really easily. However, it is safest not to let these 'leftovers' drain into the 'grey' waste-water system for ecological reasons.
I have a large white heavy duty plastic tray similar to those used to display meats in butchery departments. This also makes a great palette but of course the paint is at greater risk of drying up before you have finished your session. I get around this by putting a couple of thicknesses of kitchen paper-towel on the base and then wetting it thoroughly. Next I place a layer of baking paper (silicon coated or greaseproof) on top. The kitchen towel stays wet for quite a while (and you can re-wet as required) keeping the baking paper moist so the paint does not dry out. This 'damp palette' can also be sealed in a plastic bag overnight for use the next day.
One of the frustrating things I have found when using acrylics is coverage ... by this I mean the ability of the paint mix to cover over what is underneath. While I am often happy for the underlayer to show through there are equally as many times when I don't want it to!
TIPS for PAINT COVERAGE
Some manufacturers of acrylic paints give information on the tubes as to whether the pigment inside is Opaque, Semi-Opaque or Transparent which is very helpful. Where this information is not available one just has to find out what the pigment is going to do by trial and error.
I have found it useful to build up a collection of Opaque and Transparent versions of the main primary colours that I like to use, e.g. Pyrole Crimson (Opaque), Alizarin Crimson (Transparent), Cobalt Blue (Opaque), Ultramarine (Transparent), etc. So that I can mix an opaque with a transparent to get a more opaque primary or secondary when I need one.
To increase the opacity and covering ability of any pigment I often mix it with a small amount of White or Naples Yellow. And there are some lovely new neutral tones becoming available these days which can be mixed with other colours to make beautifully greyed tones, e.g. Toning Grey Yellowish manufactured by Atelier, and Unbleached Titanium by Matisse.
Sometimes a passage does not turn out how you want it to but, when working on canvas or board, this can often be rectified as long as the area is tackled the same day. And sometimes these remedial efforts result in unplanned and pleasing effects!
TIPS for RECTIFYING MISTAKES
I always keep a clean wet cloth and a roll of paper towel to hand while painting so that I can 'wipe out' colours as soon as possible when I feel they are not right, and for lifting runs or splashes. Sometimes it requires a little bit more effort to remove the offending area and for this I scrub gently with a toothbrush and soapy water. But this can only be attempted before the paint has truly set (under 24 hours) and I only try these methods where I am satisfied with the underlying area and want it to remain in situ. Where an area or painting has completely gone to custard I just paint over the whole thing with gesso and start again!
Happy painting! And please leave YOUR tips for using Acrylics .....