Above is a screen capture of Ultrafractal with the Mandelbrot set (Fractal 1) and the switch utility active.  The one thing you don't see is the cursor arrow, but you will when using UF.  The switch function will generate another image, in this example Fractal 2, a Julia.  To use the switch function take the following steps.

1.  Open the Standard Mandelbrot or another formula which has a companion set. If  the blue switch icon with its arrow appears greyed out the formula does not have a companion set.

2.  Activate the switch function by clicking on the Switch Icon from the toolbar at the top of the UF window....the switch window will open.

3.  Slowly run your cursor along the Mandelbrot and watch in the switch window for a shape you like....right click.  A second fractal will be generated.

Julias with great swirls can be found using the switch function by putting your cursor in the areas labled Seahorse Valley and Elephant Valley.  These are so named because if you zoom in on the Mandlebrot set in these areas, you will see spirals that look something like seahorses or elephants.  Zooming into these areas is another way of getting good spirals.

The Julia seed numbers are coordinates from the "middle" of the Mandlebrot set.  Above and to the right of the "middle" the Julia seed numbers are positive.  To the left and down, they are negative.  Find the "middle" by moving the switch icon around in the large black area of the Mandlebrot set until you see a perfectly round Julia in the switch window.  That will be a Julia with the seed value of 0,0.

For more on the Mandlebrot and Julia sets see

3 Periods of Bulbs by Professor Robert Devaney
PDG's Quick Guide to the Mandlebrot Set by Paul Derbyshire
Basic Information on Fractals by Jean Pierre Louvet