Stock market investing can be a profitable way to grow your wealth, but it can also be a high-risk venture if you don't know what you're doing. To avoid common mistakes in stock market investing, it's important to start by doing your research and understanding the basics of investing. Also, it's crucial to follow your long-term investment strategy rather than acting out of fear or greed and refrain from making emotional decisions. Another mistake to avoid is investing excessively in one stock or putting all your eggs in one basket. Finally, exercise patience and self-control because investing is a long-term game that calls for consistency and tenacity. You can improve your chances of making money in the stock market by staying away from these frequent mistakes.