People would ask, back in my biz rep days, "What should I invest in? HOW should I invest?" I told them to max out available IRAs and 401(k) plans, and do those things year in and year out. Here are some basic pieces of advice:
TWENTY WAYS TO BUILD WEALTH
1) "Patience is the fund investor's single most powerful ally." -- Benjamin Graham (My thought: Set up your asset allocation, fund it, and don't mess with it.)
2) Don't mistake a low price-to-earnings ratio for a value stock. (It might be a going-out-of-business stock).
3) "Adopt simple rules and stick to them." -- Benjamin Graham
4) Know your risk tolerance. Pick an asset allocation (stocks and bonds) that lets you sleep at night, so you won't panic and sell at the bottom. (Hint: A 100% stock allocation might be a bad idea).
5) Be tax-savvy. Hold taxable bonds in a 401(k) or IRA. Put stocks in taxable accounts. (That way you can sell losers -- be they funds or single stocks -- to tax loss harvest).
6) Build an emergency fund (mainly cash and equivalents) outside your IRAs and 401(k).
7) Put alternative investments (such as real estate) in your IRA.
8) Keep an eye on mutual fund fees. (If you pay more than 1%, you're paying too much).
9) All index funds are not created equal. Some have unconscionably high fees.
10) Diversify globally to boost your portfolio's risk-adjusted returns.
11) "Time is your friend. Impulse is your enemy." -- John Bogle
12) Use salary increases to boost your 401(k).
13) Beware personal finance experts pitching products.
14) Don't roll your old 401(k) into an IRA if you might face a lawsuit. (401(k)s offer more legal protection).
15) "Big opportunities come infrequently. When it's raining gold, reach for a bucket, not a thimble." -- Warren Buffett
16) "The key to making money in stocks is to not get scared out of them." -- Peter Lynch
17) Buy a retirement annuity cheap by delaying Social Security until 70.
18) Buy no more house than you can afford.
19) "Diversification is a protection against ignorance." -- Warren Buffett
20) "If you can't save enough for retirement, be really nice to your kids." -- Dan Ariety
For most people, an asset allocation fund where stocks and bonds are in one handy spot, or a collection of broadly diversified index funds (Total Stock Market Index; Total International Index; Total Bond Fund; Total International Bond Fund, etc.) is about all that's needed. The more complicated investing is made, the better the chance to muck it up.