I'm not sure why people sometimes ask me for advice, but it does happen. Forgetting for a moment that I have no idea what I'm doing, I try not do the "talking to a younger version of yourself" thing and instead try to listen, internalize where they are + what they want and then say something hopefully worth remembering.
Maybe I'm just bad at giving advice, but I find that my advice is mostly pretty boring. It's often something along the lines of—focus on something, stay healthy, be disciplined, build a good network, etc. These things often feel too obvious to feel like good advice.
Becuase it felt too obvious, I used to couch this with something like "it may sound simple, but it's not easy". And while that started out as more of a pithy thing to say, I've realized that the phrase itself "simple but not easy" is actually the real advice.
It's hard to see things clearly when you're in the heat of it. But when you're on the outside looking in, the answer is usually super obvious. Failing school? Go out less and study more. Want a job at XYZ company? Learn some skills and make yourself useful. Want to get skinnier? Eat less and work out more.
Again—these things sound simple, but they're not easy. They all require work, dedication, focus, and time. You don't need to do a million things to make your goals happen, you just need to do 1 thing well. And it often requires doing that well over an extended period of time.
It turns out though that most people aren't looking for real advice. What they're really looking for is shortcuts. What they're actually asking is: how do I lose weight without eating less? How do I get a job there without having to learn relevant skills? how do I get better grades without going out less?
The truth is, there is no magic. There is just hard work. And so a simple heuristic I've found is that any good advice no matter what always has this attribute: it comes across simple, but in practice it's not easy.