I'd start by educating yourself on the mechanics of the market. Read A Random Walk Down Wall Street, read Benjamin Graham, read Warren Buffett. Learn to read an income statement and a balance sheet, and look at some historical stocks with income and assets in mind. Figure out how you would manage your money if you had infinite time. Then if you want, hire a financial advisor that manages money the same way you would, except has the time that you don't to actually investigate companies and keep an eye on their financial performance.
Also, keep in mind that an index fund is effectively free financial advice (that you always follow) from every market participant. Essentially, you're saying "I don't have time to make my own investment decisions, so I'm going look at the average of what everyone else is doing, and do that." That average will include everything from Goldman Sachs money managers and Warren Buffett down to retail investors and financial advisors. It's capitalization-weighted though, so the people with the most money's "votes" count the most, which is usually what you want.