Here is a simple tutorial for creating a burst or call out shape in Illustrator. Feel free to check out my other burst tutorial here.

Start by opening a new file.

Next, use the Ellipse Tool on the tool bar to make a circle. Holding down the shift key while you draw the circle will constrain it to a perfect circle instead of an oval.

With the circle still selected, go to Object > Path > Add Anchor Points. This will add extra points to the circle.

Repeat the Add Anchor Points step until you have the desired number of points. I did mine about three times.

Next, with the shape still selected, go to Filter > Distort > Pucker & Bloat.

A dialogue box will appear. Hit the Preview check box and play with the slider until you get the shape you want. That’s it!