Debt slows you down and keeps you from achieving your financial goals. Get rid of debt because the credit card bills compound interest just like the stock market does. The longer you keep your money invested the better chance it has to grow. Never try to time the market. Nobody knows when the market will fall or when it will rise.
Nobody has ever been able to consistently predict the market, it's impossible.
Not much happens in the early years, but as time goes on, you begin to see the miracles of compounding. Don't worry about short term fluctuations or bear markets. Financial markets always recover and bull markets do return. The longer you keep your money invested, the bigger your total return will be. Put some money aside from each check.