Investing is not easy. You are trying to predict how millions or billions of people are going to act. You may think the market should go up based on some kind of news you heard, but you can't control the thoughts and actions of others.
There are a few advantages that you can gain if you understand economics, particularly free market economics. First, you should understand that economics directly involves human action. It doesn't matter what mathematical formulas you have or what graph lines you have. What matters ultimately is how millions of human beings will act.
Another great advantage for Austrian economists is the understanding of fiat money. For most transactions that are made in our world, money is usually on one side of that trade. If you have an entity (the central bank granted by the federal government) that has a monopoly over money, it is a major factor in our economic decisions. You could have companies that are becoming less profitable and the stock prices should seemingly go down. But if the government is printing money like crazy, it might be possible for the stocks to go up in price in nominal terms.
You could be earning 12% a year on your investments, but if inflation is running at 14%, then you are losing money in real terms. The kicker is, you still have to pay taxes on your 12% "gain".
Financial advisors will talk about the need for diversification. But one thing that often gets left out is diversification against a falling dollar (or other currency). This is the main advantage to understanding free markets. Because politics plays such a huge factor in our lives, even though it shouldn't, we must regularly base our investment decisions on what is happening in the political world, which includes central banking.