Unless you really want to play with buying/selling individual stocks, you're probably best off buying a broad-based index fund, which effectively buys you a slice of the entire stock market. Eg VTSMX/VTSAX
Also, are your 401k and IRA/Roth fully funded? Be sure to do that first. (Assuming USA resident here)
Also, are your 401k and IRA/Roth fully funded? Be sure to do that first. (Assuming USA resident here)