One: clear debt above about 10%#
Paying off a 20% credit card is a guaranteed, tax-free 20% return. Nothing in a brokerage account competes with that, and unlike the market it can’t have a bad decade.
The threshold sits around 10% because that’s roughly what a broad stock index has returned long-run. Above it, you’re borrowing at a higher rate than you can reasonably expect to earn, which is a losing position no matter how good your fund is.
Two: three to six months of expenses in cash#
This isn’t about returns. It’s about not being forced to sell.
An investor without a cash buffer is one boiler failure away from liquidating at whatever price the market happens to be offering that week — and market lows correlate with job losses, which is precisely when you’d need it. The emergency fund exists so that your investing horizon stays long regardless of what your year does.
Three: only invest money you won’t need for a couple of years#
Money earmarked for a house deposit in eighteen months does not belong in equities. Held long enough the market trends up; held over short windows it does whatever it wants. Buy in 2000 and sell in 2003 and you lost money in one of the great wealth-creating instruments of the century.
The three prerequisites share one function: they make it possible for you to leave the money alone. Everything else about investing is downstream of that.
Then, the actual answer#
Once those hold, the beginner’s answer is genuinely boring: buy a low-cost index fund tracking a broad market, buy it every payday, hold for ten years or more.
Why an index fund rather than picking. A mutual fund pays a manager to select stocks and charges you for it. An index fund just holds everything in the index by weight, so fees are a fraction and diversification is automatic. You are structurally protected from the single worst beginner outcome, which is being right about the sector and wrong about the company — Intel was a dot-com champion and still hasn’t reclaimed its 2000 high, while the broad market multiplied several times over.
Why cash isn’t safe. Savings paying a fraction of a percent while prices rise is a guaranteed loss in purchasing power, just a slow and comfortable one. $100 invested in the market in 1980 would be worth roughly $9,977 today; $100 of general goods costs about $360. The market grew that money around 27 times over in real terms, for doing nothing but staying in.
Where to hold it. Tax-advantaged accounts first — in the US a 401(k) to the match, then an IRA or Roth IRA, with 2026 limits of $24,500 for a 401(k) and $7,500 for an IRA ($8,600 from age 50). The Roth phase-out starts at $153,000 for single filers and $242,000 married filing jointly. Elsewhere the wrappers differ and the logic doesn’t: a SIPP or ISA in the UK, an RRSP or TFSA in Canada, superannuation in Australia. Then a taxable brokerage account for anything above that, which is flexible but taxed as you go.
Which broker. Largely interchangeable — Fidelity, Schwab, and the rest all handle the tax paperwork and charge little or nothing to trade. Pick on interface and stop researching it.
Which order type. Market orders for index funds. You’re buying for a decade; a cent of slippage is not your problem. And you can buy in dollar amounts rather than whole shares, so a $366 share price is no obstacle to investing $100.
The advice that sounds wrong and isn’t#
Here’s the part worth taking seriously if you’re starting with very little.
With $100 invested, a spectacular 10% year earns you $10. The return on learning a skill, or on building something that generates consistent income, is vastly higher at that stage — and it isn’t close. Telling someone with $100 to focus on the correct expense ratio is technically accurate advice that will not change their life.
That doesn’t mean don’t start. Starting builds the habit and the habit is worth more than the early balance. It means keep the effort proportional: fifteen minutes setting up an automatic monthly purchase, and the remaining energy on income.
The order is: earn more, then the prerequisites, then invest consistently, then leave it alone. Most people reverse it and spend years optimising a portfolio too small to matter.
So what to actually do#
- List every debt above 10% and clear it before investing a further pound or dollar.
- Get three to six months of expenses into cash and refuse to touch it.
- Check nothing you’re investing is needed within two years.
- Open the tax-advantaged account first, capture any employer match, then a brokerage.
- Set up an automatic monthly purchase of one broad index fund and don’t add a second thing.
- If your balance is small, go and raise your income. That’s the highest-return investment available to you right now.
Sources & further reading#
- 401(k) limit increases to $24,500 for 2026, IRA limit increases to $7,500 — IRS — the current contribution limits.
- Roth IRA income and contribution limits for 2026 — Vanguard — the $153,000 / $242,000 phase-out ranges.
- Does Market Timing Work? — Charles Schwab — evidence that consistent investing beats waiting, even against near-perfect timing.
