Hi, I'm name. start with a 3rd thing (that is not you or other person) like their skate shoes or shared experience like the atmosphere in the coffee shop. I usually talk to people next to me or in line, or for lunch, I sit with someone by themselves who are not too occupied.
Statements and observations are better than questions, because they have no pressure to respond. just say it and leave it out there to see if they react to test the waters a bit. Models by Mark Manson
I like X, particularly Y type of X. I like tv shows, particularly tv shows with children riding bicycles going on epic adventures. Visa
"What have you been thinking about recently?" Aaron Swartz
When they share an experience or an activity: "was there anything surprising or unexpected?" (Paul Graham asking about vacations)
When they make a claim or statement: "how do you know that?" SE
Never ask what is their major, instead: what do you like learning about? If they ask you first, don't get annoyed like me about generic questions and just answer so you can smoothly move on to: what is the coolest part about [aerospace eng]? what makes [toxicology] interesting? This works for subjects, hobbies, and interests.
Prepare talking points for generic questions: what's your major, where are you from, how do you like it here. for example, think about a cool thing in your major, in your hometown, and something that surprised you here. now explain it
I've noticed that people are the coolest when they talk about something specific that they like, and not when they're complaining about the struggle bus we're all in. So try to steer the conversation away from general stuff about academics and into stuff that gets them excited.
Negotiation: they ask for something or you want something: how am I supposed to do that? Ex: excuse me, HOW can I find the restroom? Use "how come" and "how so" rather than "why" so it's less interrogative. Never Split the Difference by Chris Voss and Tahl Raz.
eye contact: keep looking and don't look away. Look between eyes, corners of eyes, nose, eyebrows, switch between them, and blink more, so you don't freak them out. nod, smile (say "moneeeey" instead of "cheeese" to use more natural eye smiley muscles).
Listening and matching their mannerisms and body lang and stuff: "it seems like [you're saying this]." "If I heard correctly, [you said this]." to make sure you're understanding what they're saying. Repeat the last few words they just said, and they will naturally elaborate. Derek Sivers' summary of How to Talk to Anyone by Leil Lowndes. And Voss.
They say something and you think of a connection: "hey, that reminds me of [an essay]."
Putting this together: start with statements and observations, use opener questions to follow up, and then bring in connections to ideas and your experience to continue the conversation.
Bonus: Hi, I'm name. This is random, but I think you're cute. Can I give you my number?