We're all guilty of judging people at least once in our lifetimes. And actually, more accurately put, we all judge people on a daily basis. We judge them based off how they dress, how they behav and more.
It's understandable because it is in our human nature to be that way, but more often than not we are wrong about our judgment of people. When you get to know the person, maybe you realize they just can't afford to buy new clothes or have a disability they can't control.. Or maybe they're just set in their ways and that's that-- you're never going to be able to change them.
The point I'm trying to make is that we should be more concerned with our own lives and what we do so that we don't have time to sit there and worry about what other people decide to do with their own lives. Yes, you can gently encourage them to go down the right path and to try to help them change their ways, but don't get offended if they push back and start to resent you. At some point you'll need to ask yourself if it's really worth ruining a relationship over something you perceive a person to be. Worry about how you're dressed and how you're acting because no one is perfect. If you don't like something another person is doing, then you don't have to be friends with them, but you should still be polite and nice to them. If someone you know wants to go out with their friends and have a good time, and you're more of the stay-at-home type, just accept it for what it is and don't go around talking negatively about that person, because 9 times out of 10 the person you are talking about will find out what you said because, well, it's a small world after all, and it might just hurt someone's feelings.
More importantly, though, don't just take my word for it.
If you're a Christian like me, then you should know the Bible straight up tells us not to judge people. (see list of verses here) Now, before you get frustrated and roll your eyes, I'm not one of those people who throws Bible verses at people to make them feel badly or whatever, but I do want to put it out there that it is pretty hypocritical to use the Bible to justify judging other people.. We all sin. We just sin in different ways, but sin is still sin, and we'll face judgment for it when we leave this earth.
And even if you aren't a Christian, it's still important to realize what's wrong with judging other people. Other faiths point out the error in judging people as well.
So not only is it annoying for people to go around judging others all the time, it's completely unnecessary. We already have someone who will decide our judgement, and even He had mercy on us..