When i put them before characters names, should I write them in upper-case or in lower-case?

Example:

A SERVANT takes the knife.

Or

a SERVANT takes the knife.

And... Should i put them altogether?

http://www.imsdb.com/

Here's lots and lots of examples of how it's supposed to look!

I've read some scripts before. I saw different variants - with articles in upper-case and in lower-case.
I think that it isn't important. Am i right? I just want to make sure.

I think they should be in upper case, grammatically speaking, but I would also agree that it doesn't terribly matter just so long as it looks neat.

I'd think to keep it professional no matter what, good for the whole set's experience and yourself.

Unless your doing fun little random youtube videos or something and your not a partner or anything, then it doesn't really matter.