1. Don't state any facts. Don't say, "This is bad weather," even if it is. Don't say, "That shirt is ugly," even if it is. Don't say, "I'm smarter than you," even if that is a real-life fact. Don't mention that it is still dark and you are already finished with one class, but you don't remember it because you were so tired, even though that ought to be completely understandable because it is still dark outside, even if that's a fact. No one cares about facts that much usually, because they can already see them.
2. Don't verbalize your feelings. Don't shout "I'm so obsessed with you," because that will overwhelm people. Don't shout "I hate you," because it makes people hate you back. Don't say "I don't know how to be all of the things I am supposed to be," because then people feel choked by your feelings and they're like, "Uh."
3. Don't mumble. Also don't say things like, "Meh," or "Ag," instead of real words. And maybe refrain from meowing very much.
4. Don't make an inside joke (e.g. pointing at the ground, or "Totes obv awk," or "I HAVE KIDNEY STONES") because it makes anyone else who is not a part of that joke feel left out and when you've made someone feel left out you probably said the wrong thing.
5. Make the right facial expression for the situation. Furrow your brow when the conversation is about death, blood, break-ups, or math; smile when the conversation is about books, neighborhood boys, sweaters, or Matt Davis. And cats. Smile about cats.
6. Speak loudly and clearly.
7. Look at their eyes.
8. Don't mention cats. Most people don't understand the cat life.
Or maybe just scrap all of that and say the wrong thing all the time, because saying the wrong thing makes you the friends that you actually want to have and and saying the wrong thing gets you the jobs you actually want to have and saying the wrong thing is what makes people laugh and because the saying the wrong thing is what makes people fall in love with you.
All my love,