Question: How does one use CSS

[El Héroe Oscuro]

I've actually seen a few people using CSS in their posts, and I was just wondering how exactly do you use it? Plus those type of signatures where theres a picture on the left side and on the right of it they have words in a column (don't know if thats the same thing). Just wondering.

 

[Zeffy]

This thread has a lot of information about CSS, including some tutorials. :)