Question.

So, on some threads, i see that people post in a specific font and size.
Now i know you can do this when posting a thread normally like this
But some people reply to posts quickly with the same font size and everything and wont have had time to change their font and everything.
So my question is, is it possible to set your font, size before posting so everything you do post its already set and you don't need to change it?

-Thanks