I’ve written a few Top 5 posts so far, and the 5 top items have generally been listed in no particular order.
Invest in low cost stock and bond funds. Diversify. Invest early and often. Know the tax implications. Create an Investor Policy Statement with a thoughtful asset allocation for your portfolio.
Either an hourly rate financial advisor or roboadviser, such as Betterment or Wealthfront can supplement a DIY approach.
Consult with a fee-only advisor with a fiduciary responsibility. Such an advisor may charge an AUM fee (Assets Under Management), which can really add up, particularly when you have a high enough net worth to retire.
Invest with the friendly neighborhood insurance salesman fee-based financial planner, or whatever designation they are going by these days.
To come out ahead, you need to be have a sound plan, and be willing to stick to it through thick and thin. It’s not brain surgery, but gaining that knowledge takes requires some level of interest and a fair amount of time.