Just buy units in a low cost index fund every month.

The average investor must hold the market portfolio. Anything else is a zero sum game. So figure out why you are different than average. (If you think you're smarter than average, note that they think they're smarter than you.) The result encapsulates some ancient advice: Buy stocks for the dividends, broadly interpreted. Take risk you are well-positioned to take. If stocks have great value to other investors for reasons either technical (liquidity, short-sales constraints, etc.) or behavioral, avoid them. [1]

[1] https://johnhcochrane.blogspot.com/2022/01/portfolios-for-lo...