Why Jim Cramer Is Staying Wary Despite the Latest Tech Rally

Many brokers now have no account minimums and offer fractional shares, so you can start small. Regular contributions matter more than a large first deposit.

Some of the market's best days come right after its worst ones. Investors who sit out to avoid drops often miss the rebounds, which can cut long-run returns sharply.

Yield rises when the share price falls, so a very high yield can be a warning sign. Check whether earnings and cash flow can actually cover the payout.

Low-cost index funds are core holdings for many professional investors. Over long periods, most actively managed funds have trailed their benchmark indexes.

Last year's top fund or sector is often not next year's. Strong past returns can reflect luck, timing or conditions that do not repeat.

Spreading money across assets lowers risk, but it cannot remove it. In broad sell-offs, many assets can fall at the same time.