Steam milk in a swirling motion.
Knock jug on the counter to separate the foam & milk.
Swirl the coffee in one direction. Fill the milk, swirling in the opposite direction.
Start slowly in the middle, then more quickly, draw out the edge, whirling as you go, then down the middle.
Repeat the motion on one side of the centre, wriggling as you go, then down the inner side.
Repeat again on the other side of the centre, wriggling as you go, then down the inner side.
On 1 side, create a curved line, pouring a little more at the end & continuing with a quick, thin line.
Repeat on the other side.