Quoted from DanC This is gonna sound dumb, but, how does an aside work in screenwriting? ...

UNFILMABLE:
In your script you write about the Saloon: The saloon is packed with people from the town, who go there each night to unwind after a day’s worth of hard work.' That's an unfilmable, as you're aware.

That info can only be known cause you 'told' us - i.e., wrote it in the script and it wasn't expressed in dialogue.

ASIDE:
Here's a really on the nose blatant aside courtesy of Shane Black - Lethal Weapon.

“EXT. POSH BEVERLY HILLS HOME – TWILIGHT
The kind of house that I’ll buy if this movie is a huge hit.”

Asides are not filmable either.

Sometimes asides can be creative and add colour to the script. You want to go easy on them however.

The one place you can probably get away with asides is in character description, but otherwise you want to make sure they enhance the narrative flow and don't yank a reader out of the story.

Fixed my link. The damn smiley face at the end messed up the hyperlink.

Dan you used to a magic pro? Sweet. I'm an amateur degenerate myself. Were you ever on any pro tours? How long ago was this? What blocks did you play? maybe we can trade tips. Give me some magic advice and I can help you here. lol

Honestly, I don't know what half of these rules even mean, so I'm not much help.

I write the script that has this:  Orion carves his initials into a tree with a dagger.  Then someone says "no, you're doing it wrong", or I describe a scene and for some reason that's wrong.

This is why I've given up following the darn rules, lol.