Sow indoors in seed trays from late February, or if you have a heat mat from January. Aubergine seeds need steady temperatures of 21C to germinate effectively, and they like a high light intensity. Once plants have a few true leaves they can be moved on to larger pots (10cm). They can be planted out at their final spacing in April or May, preferably in a polytunnel or greenhouse. Remove growing point of main stem to encourage fruits setting on the sides.
For seed saving:
Aubergine is the only cultivated member of the solanaceae family that did not originate in the Americas, but in Asia; most likely in China and/or India. The first written record of the plant is in the Quimin Yaoshu, a Chinese agricultural work written in 544AD. Aubergines found their way into Europe in the Middle Ages through Spain and Italy, but the first record of aubergine growing in the UK was not until the 16th century.