Lower your expenses.
Nothing gets you into trouble more than having a high expense load. Get as close as you can to spending nothing.
The next most important piece of advice is to build up cash. 6 months of your monthly burn is cutting it way too close. You should save until you have at least two years. What's more, you should save until you can actually invest some money.
These two bits of advice go hand in hand. The lower your expenses, the easier is to save 24+ months of runway up. And the reverse is true too.
Beyond that, you can do a couple other things to prepare yourself. You could join a larger, profitable company with no history of major layoffs. (Eg Google, Facebook, many others.) Or, you could take the opportunity now to start your own company, and maybe think about what sorts of businesses could benefit from an economic downturn when you do so. Focus on getting it profitable, rather than focusing on rapacious growth. Obviously, these moves (getting a job at a stable company or stating a company and getting it profitable) are more out of your control and harder to pull off. Which is why cutting expenses and saving as much as possible are the most critical endeavors.