* Save at least 10% of your income. "At least," because you want both long-term/retirement savings, and a "rainy day" fund for unexpected expenses.
* Minimize your debt. If you have lots of debt, prioritize paying it down.
* If you aren't good at the first two items, create a budget, and stick to it.
Also, if you want professional advice, ask around and find a good financial adviser, particularly if you are looking for an investment strategy for long-term savings.
At the big picture level though, it's mostly about living within your income and putting some money away on a regular basis. (Someone else mentioned at least 10%.) At some level, everything else is keyhole optimization assuming some sane diversification of savings--don't put it in Bitcoin or all in your company's stock. It's useful to get other things right but they're much less important in the big picture than outflow < ~.9 * inflow (after tax).
To start simple, make sure you don't spend more than you earn (excluding exceptional circumstances). A simple table, GNU cash or even pen + paper are enough for that: record every transaction you make, no matter what tools you use, as long as it's reasonably low-friction.
I used a simple table with columns date, account, value, purpose. "account" helps getting a sum total for each bank account and for cash, to check how my table compares with reality (ie. bank statements and the content of my wallet).
Simply by tracking money flow you already learn a lot about your habits, while collecting data that helps you optimize it if necessary. I also found that making spending a conscious matter like that already reduced impulse buys.
After that, the other ideas are good ones - and you'll know if they're achievable for you and how.
1) Housing tends to be the biggest expense. So try to share an apartment with flat mates until you're sick of it, or even stay at your parents place for a few years (if that's possible).
2) If you need a car, buy a used one in good condition and keep it that way for many years. Make sure you change the oil and filters at recommended intervals.
3) If you like to travel, learn to do it cheaply! Long and wonderful trips in south-america or asia can easily be had for 1000$-2000$ a month - sleep in hostels, eat what the locals eat, don't drive/fly around to much, travel slowly. :-)
4) Learn to cook.
5) Learn to make and fix basic things around the house: installing fixtures, plumbing, wall painting, furniture (fixing and making), etc. Doing things yourself is more satisfying and saves money.
All good advice in the peer comments, when I was in my 20's I was putting the maximum I could in a 401k (pre-tax), and putting 10% of my salary into the employee stock purchase program. Before we had kids my wife was putting most of her salary into savings for a down payment on a house. Unlike many of my peers I was bringing my sandwich in for lunch (still do that). I tend to own cars for 5+ years, I don't take annual vacations to places I have to fly to (hiking and camping is pretty inexpensive and easy to do in California) and generally I always try to keep my monthlies (phone, power, tv, internet) under control. Every month payed off the credit card (used for book keeping more than credit) and cook food rather than buy pre-prepared food.
I don't know about links, but the basics are simple enough: track what you spend and save some % of what you make. Avoid debt for things that lose value (e.g. cars). Debt for things like houses that retain value can make sense, though. Always keep money in reserve. Pay off the high-interest debt (e.g. 30% APR credit cards) first. If you do buy any complex investments, keep in mind what conditions cause gain or loss. For example, I recently saw an annuity/ETF product where they let you invest in indexes and cover the first 10% of any losses, but you gain at most 10% annually (they get the rest). It took me a while to realize that this means you get a 10% upside and 90% downside.
I'm sure others can give you more common sense advice.
> Avoid debt for things that lose value (e.g. cars).
This is actually not terribly good advice. Debt does not become especially bad depending on whether what you used it for is gaining or losing value.
This rule is really a proxy for, "Don't buy an expensive car, boat, or plane, relative to what you are making." Now that is a good rule. There's no reason to hide it behind a false rule. Financing a purchase that you could pay cash for can sometimes be wise, even if the purchased item is losing value.
If you fall on hard times, you can sell things. If you have to sell something like a car that lost value, it won't be as good as being able to sell something like a house that holds value.
Debt is evil. Unless you can get a higher rate of return than the interest rate of your debt, pay off the debt as soon as possible.
Have at least 6 months of expenses in an easily accessible, liquid place like a bank account. Once you've got that rainy-day fund in place, plow the rest (at least 10% of income, 20% is probably a better target) into investments and take any tax advantages possible:
Traditional IRA + Roth IRA ($5500 combined max/year)
Traditional IRA contribution is tax deductible if you aren't covered by a work retirement plan or if you're under a certain earning threshold.
Take advantage of 401(k) if your employer offers it, contribute at least enough to get any matching they offer. These are pre-tax dollars, but some plans have shitty investment options, so YMMV. $17,500 max/year.
Put the rest in an individual brokerage account and invest regularly (monthly or quarterly) in low-cost, broad-market index funds or ETFs like VTI, VOO, or QQQ.
The rest is your fun money...you're young, so make sure you're also investing in yourself by going on trips, having fun experiences, etc, just keep the future in mind and don't go TOO crazy!
It's, among other things, a consumption smoothing modeler (i.e. make sure that you don't oversave or overspend). It will tell you about how much you need to be saving each year, given a bunch of variables like how much you make, how much you plan to make, etc.
If you work as a programer or similar, your salary will probably increase significantly over the next 10-20 years. Your spendings will increase over time as well.
If you are not crushed by debt, just try to make your spendings increase much slower than your pay.
* Save at least 10% of your income. "At least," because you want both long-term/retirement savings, and a "rainy day" fund for unexpected expenses. * Minimize your debt. If you have lots of debt, prioritize paying it down. * If you aren't good at the first two items, create a budget, and stick to it.
Also, if you want professional advice, ask around and find a good financial adviser, particularly if you are looking for an investment strategy for long-term savings.