This is a video with which Leila Arzani uses a small vessel, I think a mug, and pipettes various color droplets to create a form of rainbow marbling. She uses a stick to guide the flow of pattern within the marbling which she is trying to achieve so that when she has the result she is after she can then pick up an artificial nail and quite literally dip it directly in to directly replicate the design. A very interesting video which looks like good fun to do.
This detailed video series shows from start to finish the principles you would need to adopt to create your own ceramic mug. It covers techniques like centreing, throwing, preparing a lug etc, and talks you through the tools used and how they work. A very concise video which will have you a pottery pro in no time.