Last week, I discussed how to begin a story with a descriptive opening; however, not all stories have to start that way. Another way to open a narrative is with dialogue. There are several ways to go about this, and I'll list some of them below. First, you can open the story with two characters speaking or several talking among themselves. Keep in mind that the main protagonist and/or main antagonist don't have to be present for this. The conversation can be between very minor and/or less major characters. Their discussion also doesn't have to be about other characters in the story either. Rather, they can be describing an event or setting.
Another option is to have multiple people talking, but the conversation occurred in the past, or it can happen in the future. Writing about a past event can help set the tone for how things are in the present or how they came to be that way, and it can be a brief dialogue opening too so that not too much is given away. As for the future, it might function as foreshadowing something to come or a possibility in the story that might be preventable.
The last option I'm going to mention here is having a conversation in a character's head, or the character is talking to themselves out loud. This can happen in the past, present or future. Again, this character can be any character in the story; it all depends on how you want to start your narrative. If they're talking in their own head, I often use italics to help distinguish this. And if it's out loud, just keep in mind that you're going to want to keep that consistent through the story unless you plan for that character to stop that habit later on, but make sure that you have an explanation for why. Otherwise, it'll be somewhat awkward to have your character speak out loud once and never have it happen again unless they were talking to themselves in the past and they don't anymore in the present world.
So, those are some of the options, but how do you make the dialogue catch attention? On that note, it's somewhat similar to last week's post. Imagery matters. Yes, people are talking, but they can create a setting with their words. For example if you're writing a mystery novel and there's been a recent death, have characters discuss what they've heard or learned about it. If they're minor characters who are talking before the protagonist makes their debut, maybe, have them mention a news report as though they're gossiping about it. Whereas if it's the protagonist and a medical examiner, they might describe the death in more detail at the scene of the crime since they're viewing a more graphic display of it. Regardless of which characters are talking, have them mention what they're seeing, smelling, etc. to create a more vivid and capturing opening for your audience.
Along the same vein, adjectives will aid the above imagery. However unlike a descriptive opening, keep in mind that it's okay to repeat words in a sentence and use more common adjectives found in speech since conversations tend to have less formal words in every day life. Granted, keep the time period of your story in mind too since that will change speech patterns and what words were/are more frequent. Anyway, I hope that this helps!