McMoRan Exploration is the gambling man’s natural gas play, Cramer says. Here's why.Investing can be confusing. Luckily, Cramer has mapped out some road rules for all you Home Gamers trying to navigate the jungle that is Wall Street. Think of it as "Mad Money 101" –- some fundamental advice to keep in mind as you play the market. Whether you're a first time investor or a seasoned financier, it's always good to remember the basics.