The One Skill Nobody Teaches You When You Finally Become an Adult

Nikolas Stavrou

Nikolas Stavrou

— 9 min read
The One Skill Nobody Teaches You When You Finally Become an Adult

Your salary doesn't matter. What you keep does.

I'll be honest. I went back and forth on whether to write this post. I mostly try to keep the blog tech-related, and I'm definitely not a financial advisor but I said I'll give it a shot and write on the things that troubled me in the recent months since I am very content with the outcome. This is just my personal take. But the more I thought about it, the more I realized that personal finance might be the most important skill when it comes to actually becoming independent as a grown-up. And I think a lot of people in their 20s are struggling with it way more than they'd admit.

I spent a significant amount of time last year learning everything I could about managing money: how to save, whether to invest, and if so, where. The topic is massive and could easily turn into a ten-part series. So instead of going deep on everything, I'm going to keep this to the core principles and what I personally figured out. Where something already exists and explains it better than I could, I'll link to it directly. No need to rephrase what's already been said well.

The Moment It Gets Real

Here's the situation most of us find ourselves in at some point: you finish your studies, you get a job, your parents stop financing your life, and suddenly you're paying for everything. Rent, groceries, utilities, restaurants, entertainment, everything adds up fast. And if you're not paying attention, you can very easily end up spending way more than you should without even realizing it.

The basic idea is straightforward. You earn a salary. You use part of it to cover your living expenses. And then, ideally, you save some of what's left. You save for short-term goals, like a vacation or a nicer computer, and for long-term ones, like a car or eventually putting down a deposit on a house. Simple enough on paper. Actually doing it consistently? That's where it gets tricky.

I found a huge amount of help from the r/personalfinance wiki, which I'd genuinely recommend reading if you haven't. Some parts are more US-specific (tax-advantaged accounts, retirement funds, etc.), but the general framework of budgeting, building an emergency fund, paying off debt, then start saving and investing, applies pretty much everywhere.

The Uncomfortable Truth About Starting Points

I want to address something that I think doesn't get talked about enough: your family situation plays a massive role in how your financial life starts.

Think about it. Imagine a person who graduates already carrying debt, can barely make it month to month, and is trying to pay that off before they can even begin to save. If you run the numbers on an average European salary, you'll see that saving a few hundred euros a month means it could take your entire life to scrape together enough for a mortgage, which you'll then spend the rest of your life paying off.

So here's my number one piece of advice, and it might be unexpected: if you're a parent or planning to become one, invest in your child's future early. Make sure they can get a proper education without going into debt. If possible, set aside some money for them while they're young. As far as I know, there are savings accounts for children with better interest rates that work well for this. That money can serve as their emergency fund when they start out. No debt, a good education, and a financial cushion means they can start saving and investing from day one instead of spending years digging out of a hole first.

I was fortunate enough to be in that position. My parents aren't finance experts or anything, but they understood the basics of saving. They financed my studies and accommodation abroad and made sure I had some money set aside by the time I started working, partly from their own savings, partly from me being careful with what they sent me during uni. Because of that, when I got my first full-time job, I was able to start putting money aside immediately for travel, for long-term investing, for side projects, all while still living comfortably.

Now, obviously, none of this is in your control if you're not a parent. And not having that head start isn't the end of the world. I'm pointing it out because it's real, it matters, and pretending everyone starts from the same place doesn't help anyone. Whatever your starting point, the principles still work, they just take longer to kick in.

The Only Principle That Actually Matters

My dad used to tell me something that stuck with me: it doesn't matter if you're making €1,000 or €100,000, what matters is how much you have left at the end of the month. A person earning €1,000 and saving €100 has more money saved than someone earning €100,000 and spending every cent of it.

That's the whole game. You need a surplus at the end of every month. It doesn't matter what your income is. If there's nothing left, you're not making progress. And from what I've seen so far in my circle, most people don't actually have a clear picture of what they're spending. That's the first thing that needs to change.

How I Actually Track My Money

There are plenty of ways to start budgeting, and I'll keep this practical.

If you're using a modern bank app like Revolut (or any neobank, really), you probably already have a basic budgeting system built in. Transactions get categorized, you can set spending limits per category, and you can see where your money's going at a glance. That's a perfectly fine place to start, and it's what I used initially.

But personally, I wanted more control. That's how I ended up switching to Actual Budget, which is an open-source, privacy-focused budgeting app that uses the envelope budgeting method. There's also YNAB (You Need A Budget), which is popular especially in the US, though it requires a subscription. I'm not advertising anything here, just sharing what I use and what I've seen others use.

The idea behind envelope budgeting is simple: you assign every euro of your income to a specific purpose. Groceries, rent, entertainment, subscriptions, savings, each one gets an "envelope." When you spend money in a category, it gets subtracted from that envelope. If you overspend in one area, you have to move money from another envelope to cover it. You can't just go negative and pretend it didn't happen. It forces you to be honest about your spending.

Setting up Actual Budget does take a bit of initial effort, maybe a day or two if you're comfortable reading documentation and doing some light setup (it's a self-hosted app, so there's a small technical barrier but nothing crazy, you can follow their hosting solution on PikaPod for around 1 euro / month. But once it's running, it's smooth.

Here's what it did for me in practice. I created categories for everything, groceries, rent, restaurants, shopping, subscriptions, travel, side projects, investing. Almost immediately, I noticed things. I saw exactly how many subscriptions I was paying for. I realized I was spending too much on eating out, so I cut that down.

The result? I'm now able to save approximately a third of my salary. For someone who recently started working full-time, I'd say that's a solid starting point. But more than the number, it gave me a kind of organizational clarity I didn't have before. I can save for travel, set aside money for side projects, and invest, all without guessing.

What I Do With the Surplus

Once you're saving consistently, the question becomes: what do you actually do with that money? I think some of it should go into investing. Without going into too much detail here (maybe I'll write a separate post on this, let me know if you're interested), here's my current approach.

I invest my long-term savings into an all-world ETF, specifically one that tracks the FTSE All-World Index (like VWCE). To keep it very simple: it means you're buying a small piece of stock from the top-performing companies across both developed and emerging markets worldwide. The allocation is roughly 63% US, about 6% Japan, and the rest spread across the UK, China, Canada, and others. The money I put in there, I'm aware I won't touch for at least the next decade.

From everything I researched, this felt like the most sensible approach for now. It might change in the future, but when you look at your options for growing money, they basically boil down to: invest in the stock market, buy assets that might appreciate in value (real estate, collectibles (which is tricky and requires research)), invest in yourself and your skills (sounds cliché, but it's probably the highest-ROI move you can make), or invest in a business or side project.

That last one is actually why I keep a small, separate budget for side projects. It's not a huge amount, but it gives me the freedom to try things without overthinking it. For example, the domain for this very blog, paid for with my side project budget. It's a small thing, but being able to make those moves without stress is exactly the point.

Why Starting Early Matters

I wasn't really aware of how much thought personal finance requires until about a year ago. But in essence, it's actually pretty simple once you start doing it, and the earlier you start, the better.

If you start investing early, you get the benefit of compounding over time (assuming the world still exists when we're older, but let's stay optimistic). And beyond the financial math, the habits you build now get harder to establish later, especially once you start having kids, sharing expenses with a partner, or dealing with more complex financial situations. If you're cohabiting, by the way, I'd really encourage setting up shared expense tracking with your partner. It makes things so much smoother down the line.

I think the ideal scenario would honestly be for parents to start teaching these things when their kids are young, in a simplified way. I remember being maybe six or seven years old, getting about two Cypriot liras from my parents for school lunch. I'd buy a halloumi bread and a chocolate milk, and I'd still have about 50 cents left over. So naturally, I'd go ahead and buy a stack of cookies at five cents each and hand them out to my classmates. Philanthropy before I even knew the word, I suppose. Not exactly the savings lesson my parents had in mind, but the spirit was there.

The Part Nobody Talks About: It Feels Good

Here's something I didn't expect. Tracking my money doesn't feel restrictive at all. It actually gives me peace.

When I know my budget for the month, say for eating out, I know exactly when it makes sense to go to a restaurant and when it doesn't. I can choose to spend €5 on a quick meal one day and €40 at a nicer place another day, and in both cases, I know where I stand. I've never once felt like I was pressuring myself to cut back or restrain my spending in a way that made me unhappy.

I think that's because awareness changes your behavior naturally. When you know the numbers, you just make better decisions without even thinking about it. You stop being an impulsive buyer, not because you're restricting yourself, but because you simply see what's happening. It's less about discipline and more about clarity.

Wrapping Up

Personal finance isn't glamorous. But I genuinely think it's one of the most impactful things you can figure out in your 20s. The core of it is dead simple: know what you earn, know what you spend, make sure there's something left, and put that something to work.

If you're already doing this, amazing! Feel free to drop a comment and tell me how you approach it or how I could improve my system. If you're not doing it yet, start. It doesn't need to be complicated. Even just looking at your transactions from the past few months and categorizing them is a solid first step. I would also recommend everyone to take a free course online on wealth management as they grow older. It is definitely something on my to-do list for the upcoming years.

I might do a follow-up post diving deeper into the investing side of things. If that's something you'd want to read, let me know.

Take care, and stay in the loop.

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