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