Directed-form or free-form?
Hans Hoffman's use of colour and improvisation are striking. I have found that in creating abstract works of art it is essential to know when to stop, to feel ones way into a painting, looking for balance of form and substance, but essentially to know when to stop. There is a certain amount of energy put out during the artistic process, which I believe is limited and cannot be forced, a certain time for creativity to seep through.
I found that I have been working in two distinctly different ways, one which is directed-form (my news article interpretations and photography) and the other one is free-form (abstract paintings) where the colour and brushstroke that lead the way. The latter is much more challenging, but just as rewarding and surprising when it turns out well.