Hi there, firstly welcome from Oz. On the topic of pre washing your fabrics, I tend to wash only now the dark or brighter colours because you'll learn very soon that they'll run like crazy if you don't. Sometimes I add some salt as well, to safeguard against running depending on the country of origin. Good quality fabrics do not need to be pre washed but some could do with added softness to the outer layer and to break down fibres for easier quilting, in the case of polished cottons. Avoid polyesters for quilting as their colour fastness and stretchiness can surprise the best of us! Above all, happy sewing and experiment for yourself! Best Wishes, Therese