Up until a few years ago, my personal portfolio looked a lot like everyone else's. I had money invested in the S&P 500 as the core of my portfolio. But beyond that, it was a mix of style, sector, and factor ETFs without a lot of focus except for the fact that I thought they had a good chance at being outperformers.
There were some hits and misses, but the thing that prevented me from having more success is that I just didn't pay attention to it as much as I should have. In the end, I wasn't really generating any meaningful outperformance and I just owned a portfolio of funds without much structure.
So I decided to instead focus on just two things I could control: simplicity and low costs. The big selling point of index funds was that instead of paying high expense ratios to try to beat the market (and most money managers don't), just buy the index, match its performance, and pay next to nothing for the privilege.
So that's what I did. I put the majority of my portfolio into two ETFs -- the Vanguard Total Stock Market ETF (VTI 0.38%) and the Vanguard Total International Stock ETF (VXUS 1.24%). Looking back now over the past three years, I can say that it was one of the best investing decisions I've made.