Best "Witness"strategies for mining ?

Hi All,

 I was wandering  what are the best ways of using witnesses when mining, as it is no clear to me.....

I can use any steemit account name as a witness right? but also there is a list of TOP witnesses here in the steemit website. 

Do witnesses get paid from my mining ? I can also use my own name as a witness, but I read is good to use other names/ accounts as this gives you more places in the queue ..Can anyone clarify, please?

Many thanks.

/Anarcharos.