"Sweet lord!" Jackie exclaims as he slams his hands on the metallic safe. "We are rich, boys and girls!" <<------ Open the conversation how you wish to, the first line usually sets the stage so an appropriate starter works. Here we are staging the scene with a safe and Jackie being the first to speak, as he is forefront and center at the safe.
"Not yet, mister!" Jane struts over and places her palm on his hand, holding it down. "Not until it's opened and confirmed." she sternly says as she darts an eye at the man. <<------ Here we introduce our 2nd character, Jane. We begin by establishing a tonal difference in speech, even without reading the name, you can tell that this line is a direct response so it cannot be from the same person as before, we also begin to establish someone who speaks with a different sass.
The room goes silent, as the man and woman clad in bank guard uniforms by the side of the room take a few glances at each other and break out into a giggle, before turning their gazes towards the safe as well. <-- In the third line, we re-establish the setting, building the stage further as we introduce more details about the environment. We introduce characters 3 and 4, and make a distinguishing point about them, being that they are clad in bank uniforms, and also that they are at a distance from the safe, away from both Jackie and Jane, who are physically close to the safe. Having characters too close to each other can cause problems with distance when you start writing actions.
"What, you too?" Jackie jests as he winks at the couple, his hand playfully reaching for the safe's door handle. <<------ We return to character 1. Remember that he exists! And as the central character of the stage at this point, we further his actions and reconfirms that the couple is not the same people as Jackie and Jane, by having him talk to them and give a wink.
"Open it." the woman smirks, her arms folded as she folds the crease of her uniform back neatly. <<------ The couple replies, and here we use 'the woman' instead of a name. This is important, because we have introduced her as a woman without a name. If you have not established a name linkage, do not throw a name without prior setting up! Also, we mention the uniform again, so your brain recalls the character with the uniform.
"Remember, 40 percent." Jane affirms as she taps a few times on the metal safe before backing up a little to watch the reveal. <<------ We reintroduce Jane, as she is standing by the safe and haven't spoken a line in a while. Again, we make her do something at her physical location. Locating your character is helpful as readers will have a visual reference of where everyone is in their heads.
Jackie firmly grasps onto the cold handle, as he pulls his entire body backwards while yanking at the safe door. <<------ Back to Jackie. No lines spoken, this is a driver to push the scene forward.
"Dumbass." a gruff voice interrupts his failed attempts as Chris steps up to the safe with a crowbar in hand. <<------ A new character joins the conversation! We use 'a gruff voice' as it immediately tells the reader that this is an unknown character that has not been set up properly yet. Here, we use Chris, assuming he has been introduced earlier in previous scenes. We also attach a location to him, namely the safe.
He pushes Jackie off to the side, lifts the sleeves of his white shirt up, then slams the crowbar into the handle, hooking it to provide leverage. <<------ Continuation, we also give him a white shirt. Help your reader build the scene!
"Hey, tough guy!" the uniformed woman shouts. "If you break whatever's in the safe as well your body is going into that safe too!" <<------ Again, the uniformed woman speaks. Also, shouting is used because she is physically furthest from the safe, where the majority of our characters are, this helps to further reinforce and exploit the use of location.
Chris turns his head to the woman and nods. <<------ Chris responds. No words. Connecting action.
"Always the one to save the day, huh?" Jane smirks. <<------ Jane speaks again! Notice that Jackie has been left out for a while, this is okay, because Chris has replaced Jackie both physically by pushing him away and stepping up to do the job, as well as in writing when he takes over control from Jackie. It doesn't matter what happens to Jackie now. Again, remember Jane's sass, her way of talking. Keep consistent!
"Amigos, why you so angry, we all friend, yes?" the man with the uniformed woman speaks as he shrugs his hands into the air. <<------ man with the uniformed woman, this is a test, and if you guessed the other uniformed man beside her, you are correct! We have located them alone by the side, so you would think of him first. He also speaks very differently!
"Finally, the mute speaks." Jane scoffs as she rolls her eyes. <<------ This woman! Although what is done here, is that we are using Jane to confirm that the man before this line has not spoken at all, so it cannot be any of the other characters.
Chris flexes his muscles, stretching them as he grabs his crowbar and pulls hard on it, pulling the safe open in a decisive swing. <<------ End scene