[LVL ED] Tips for lighting

[The chaser]

So, I'm working in a very serious CS, and I would like some tips from this forum. I work a lot the lights, but there's always something basic that makes them look ugly. I even make cool lights sometimes, but I would like to know:

-How creating, designing, and putting correctly a billboard
-Particles (which I should use)?

And others. When this thread is complete, I will ask someone to move it to development articles, because lighting is something basic for a story, and maybe somone founds the tips useful. The time where my CS is right now is at night. I would appreciate too tips for day and night.

Have a nice day!