Finances are difficult to manage. My wife is also in school so we have no income. I saved money prior to school and took a travel assignment immediately prior to quitting work for school. This was a great way to save some money. I made sure I had enough in my savings account to cover our house payments for the entirety of the program. As far as living expenses go, we rely on loans. We're fortunate to have family to help us out with small expenses too. The loans are generally enough to cover expenses, but they're not limitless. Some of my classmates with kids have an extremely tight budget. Other classmates have also had to take out private loans. It's doable, but I personally think the financial aspect is the most difficult difficult part of anesthesia school.
As far as preparation, enjoy your free time while you have it. I know everyone says this. I too wanted to dive into concepts that would better prepare me for school. I studied a little bit before starting and it didn't help. They will teach you what you need to know. My program has a chemistry course incorporated that was anesthesia specific so I didn't spend any extra time on chemistry. Take a vacation, sleep, enjoy time with family, and be ready to hit the ground running. It is hard, but doable. Some students on here are so discouraging. I was scared to death before starting. I still have free time, just not near as much as I did before or even while in nursing school. We start our "real" clinical in the spring so I may be eating my words, but the didactic portion is all about time management.