Don't Casually Dismiss Feedback On Your Social Skills
One of the mistakes I've seen socially inexperienced or awkward people make is being too quick to ignore feedback on how they're coming across. For example, a guy makes a tasteless joke, and his friend tells him it's inappropriate. He casually brushes the critique aside with a, "Nah, that joke was fine. I didn't mean anything bad by it." He replies so quickly that he obviously didn't even consider what was said to him. He just instantly assumed he didn't do anything wrong. It's like the possibility that he might flub part of a conversation isn't on his radar.
It's not a good idea to blithely, obliviously disregard comments that you might have made a social mistake. First, it's just possible you committed an error. No one's perfect after all. Your own judgment about whether you went wrong or not isn't necessarily accurate either. One symptom of social inexperience is that you don't have a well-calibrated sense of how you're performing. You don't have enough knowledge to be able to make that call.
Next, many people will only point out a faux pas if they think it's on the more-serious side. They'll let smaller things slide. They realize everyone makes minor gaffes from time to time, and don't think it's worth drawing attention to all of them. They also tend to give others the benefit of the doubt. If someone says something that seems a bit tactless, but it could be chalked up as an accident, they'll lean toward seeing it that way. A lot of people also shy away from confrontation, and won't want to potentially hurt someone's feelings or get into an argument over a little slip up.
Basically, if someone's taken the time to say you were being inappropriate, they did it for a reason. That's true even if they delivered the message in a non-forceful, non-angry way. As I just said, many people don't like confronting others or making a scene, so even if they think you did something wrong, they may still try to tell you in a polite, nonchalant, or joking tone.
If you get this kind of feedback, it's not necessarily that you made a terrible mistake, or that you're an irredeemable, horrible person, or that no one will ever want to hang out with you again. It's just that you did one thing that other people felt was worth pushing back against. All I'm asking is that you take some time to reflect on what they said, rather than instantly dismissing it. Override your first instinct to tell yourself, "I didn't mean it like that" or "Ah, they're just overreacting."
Like say you comment on a friend's new haircut and they reply, "Ha ha, wow, that's a tad mean-spirited!" They didn't say that out of the blue. Think about the remark you made. Maybe you'll conclude you genuinely said nothing wrong, and your friend is being too sensitive. That's fine. Not all feedback is going to be right. But at least you gave it some thought. Or maybe you'll realize your comment had a passive-aggressive edge to it. And maybe you'll dig even deeper and admit to yourself you have a bad habit of taking little jabs at people's appearances, because you're insecure about your own looks. Again, that doesn't mean you're a 100% awful person, but you have identified a piece of yourself to work on. The more open you are to feedback about your social skills, the quicker you'll be able to spot and smooth out your rough edges.