Use the Width Tool to edit the taper of the stroke. First up, in Illustrator, create a circle with no fill, and a 1px black stroke.
Using the Direct Selection Tool (A), select the lower left section of the circle, and press delete to remove it.
Select the Width Tool, and click and drag a section of the stroke near the tip.
Now use the Width Tool again to click and drag another section a little further down the circle. This time, drag the tool inward.
Repeat this process over and over, resizing and rotating the curves as you go to create an ornate swirl illustration. Experiment with this tool and see what kind of strokes you can create.

Swirls Gallery

vector swirl

typography swirls

swirls in motion

Swirls And Twirls

swirls

swirls

swirls

red swirls

london swirls

hypnotic swirls

Flower Swirl

colour floral swirl

Circles Swirls

card design swirls

brown swirl

black and white swirl

Video: swirls in action



 

Now you can repeat this process over and over, resizing and rotating the curves as you go to create an ornate swirl illustration. Experiment with this tool and see what kind of strokes you can create.



Swirls in action