To me I think about "investing" as trying to guarantee a return over the long haul. All the smart evidence points to taking a strategy that links you to index funds. This is what I ended up doing in terms of carving up my investments https://www.bogleheads.org/wiki/Three-fund_portfolio
When I started this though what I actually, of course, wanted to know more about was the sexier, potentially much higher return end of "picking stocks". This is still sexy to me, and I still get inclinations to pick stocks every now and again, particularly in the tech sector where I feel like I have an edge. But as I've done dummy investments in the past, the market has bitten me in lots of unexpected ways. General market downturns, edgy sentiment around quarterly earnings, bad product releases etc. etc. So now I call this what it is: high stakes gambling. I do play, but with money I'm ok losing. The kids college fund goes uses the three fund strategy described above making heavy use of index linked funds.