Question

What is the best selection of punctuation characters to represent a swear word?

Answer 1

I believe that a*sks are usually used if you want to imply an actual word, but &#ing random symbols is usually more comical while less offensive.

Explanation:

There is a wide selection of symbols which can be accessed using combinations of the shift, option/alt (at least on mac), and number keys.
Shift+Number: !@#$%^&*()
Option+Number: ¡™£¢∞§¶•ªº
Shift+Option(alt)+Number: ⁄€‹›fifl‡°·‚

Plenty more can be found with letters and punctuation keys.\

Asterisks are effective because they are simple and make the provided letters easy to read.