I am not entirely sure what you are heading for here but might as well. Have had to teach these to various people younger than me, have strayed from them myself at times and paid for it,
Economics right now for most places represented by this forum is pretty brutal and only going to get worse. Or if you prefer most mortgages are not going to allow more than about 4.5x your annual salary so trying to get that (never mind save up for a deposit) to get a house is hard. Play it if you want but if it is an impossibility then why sweat it? At the same time learn what compound interest is -- if you can save while young it is so much easier than doing it while older ($1000 a year at standard 8% growth is not an extra $10000 plus a little bit if you start at 20 rather than 30 but .
https://www.thecalculatorsite.com/finance/calculators/compoundinterestcalculator.php
$1000 a year at 8%
30-65 is $184000
20-65 $378000
It cuts the other way as well -- that 8% is not just a bit of comparative pocket change but brutal if you are being charged it.
Still some of it is a bit trite but all things I live by.
Learn to cook. Eating out is expensive and unhealthy. Cooking is easy once it clicks.
Learn to fix things. This might be harder for some but it saves so much money. If you can't do that then figure out whether something is a good deal -- "buy once, cry once" is a thing, as is "buy cheap and if it breaks then buy good" as general philosophies to make life better on this, and learn when things need fixing before they become bigger problems and what can be pushed out for a while. Cultivate a group that represents most things in general trades if you can.
Sort your health out as best as you can, mental is also very much downstream from physical so bear that in mind. Being unhealthy is expensive. You don't need a gym -- pick heavy thing up, put heavy thing down, repeat, grab onto bar and lift yourself up, walk long distance/jog long distance/cycle long distance is easy just about everywhere. It sucks as the ones that did not expend the energy back in the day needlessly were the ones that survived whether others starved, but we are not on the savannah any more.
You can be smart as fuck but if nobody wants to know you then you will not get far. More generally it is not what you know but who you know, and a man's word truly is his bond. If you can reliably make someone's life easier, preferably someone that is generating money, they will fight to keep you around even if you are not the best out there. Meeting people as an adult is hard in a lot of places but is possible -- work, clubs, events... possibly interest related. Learn to recognise smart people and good people if you have not already.
Keep your ego in check, can be hard for someone that lacked a moderating influence (there is a reason such people are massively overrepresented in prisons, looney bins and graveyards) but that is what you would have been taught. Even if you win the fight you might still end up injured and in court explaining yourself, and you never know when someone has a weapon, friend or skills you don't know. Don't be a target either -- despite being current space year and not caveman times most bad things happen out after dark so limit that if you can*, doubly so if you are going to be impaired, though better to be judged by 12 than carried by 6. Related to that is drive or operate road vehicles defensively, or more generally drive like everybody else is an idiot (they often are) and keep that ego in check -- you will get there when you get there, let the impatient one in/leave a gap for them (if they have to try to cut in down the line then everybody suffers, your gap might prevent that).
At the same time don't allow yourself to be walked over -- if you can squeak together a "fuck you" fund that allows you to sort a new job if someone is making it untenable then do that. Mechanics would have it as a phrase along the lines of "your toolbox has wheels on it for a reason". Related to this is salary negotiation is a game and so very few know they even playing it -- how much do you make the company or are you a cost, how much is it going to cost them to find someone new (recruitment is not free, far from it) and train them up.
Learn when a company is about to go pop and play it accordingly -- first mover advantage is a real thing in these scenarios.
If you don't have money left over at the end of the month then time to start making a budget, indeed might as well do that more generally. Might make you feel small or failure but ignore that feeling**.
I am also a firm believer in every man needs a vice (preferably the tool as well) -- being straight laced all the time is boring, just make it a good one like computer games, model kits, the occasional cake, fun books, cinema... rather than tobacco, alcohol.
Don't be a fool, wrap your tool -- someone buying a $100000 car on 20 year loan when they are barely about to keep it together would be called a fool, guess how much it costs to raise a kid? Likewise don't stick it in crazy even if you are in a bit of a slump (statistically speaking most people are) or you think it is the best you are going to be able to get, if nothing else don't propagate crazy down the generations.
*for whatever reason I am pretty tall, built like a rugby player, carry about 3 knives at any point (they are tools I use extensively), have been taught exactly where to stick them over many years if I need to hurt someone, have a repeatedly demonstrated ability to keep my head when it all goes down, have observed for threats so long it is subconscious (same for improvised weapons), usually have multiple exit plans for any particular location and the wider area (which I generally know very well if I am there for any great length of time), wear size 14 US steel toed boots basically everywhere and consider 5 miles at a pace most jog at a casual stroll. I still limit my going out after dark to that which is necessary.
**related
