All the installed designs are shown in the right-hand panel.
If you want to see a larger preview of what one looks like, hover your mouse over it, and preview will appear on the left.
Once you have found a pattern you like, click on it to select it.
You can also use your own images for patterns. Above the pattern browser is button labelled 'use custom image...'. Click this, find the file you wish to use, and then click 'open'. Please note that the included patterns, as well as the downloadable ones are designed specifically for Artisan. Using a custom image may not look as you expect.
Colours are chosen from the colour bar at the top. If you want to see what your chosen pattern looks like in a particular colour, hover your mouse over the colour. Once you have found a colour you like, click on it to select it.
You can also create interesting shaded effects. To do this, click on 'shaded', above the colour bar.
Here you can choose two colours. One colour will blend into the other. You can change the direction the colours blend together by clicking and dragging the angle dial.