After watching his parents struggle with their finances growing up, 23-year-old Zac Bissonnette has learned a great deal about how not to manage his money.

In his new book, "How to be Richer, Smarter and Better Looking than Your Parents," Bissonnette outlines the money "do's and don'ts" to help teens and young adults be financially savvy from the get-go. But his money wisdom is not just for kids. For example:

• Learn to say "no" to yourself at least once a day, especially when it comes to impulse buys, and understand that if you can't afford it, you don't deserve it.

• Buy used or cheap clothes, because expensive clothes do not always translate into better quality. And wash your garments in cold water to make them last longer.

• Take up hobbies that do not cost much money and are not materialistic, like gardening.

• Serve cheap, discount store wine, at parties and do not buy imported wines, which can sometimes cost up to 50 percent more.

• Buy groceries on-line or in bulk and buy a slow-cooker to prepare meals.

The most important message he hopes people take away from the book is that money cannot buy happiness, as indicated by a lot of empirical evidence. "The most powerful thing that money can do for you is reduce stress in your life," says Bissonnette, who is also the author of Debt-Free U. "The more debt you have the more likely you are to be stressed out."

Here are three additional money lessons he highlights in the book:

FICO Scores Really Don't Matter

There are countless stories outlining how to calculate and achieve the perfect FICO credit score, but Bissonnette says you should not fixate on your rating. (See: How Your Credit Score Is Calculated)

"The one really good thing, that I don't dispute, that you can do with a good FICO score is buy a house with a fixed-rate mortgage and get a lower interest rate that can save you a ton of money over the life of the loan," he says. "But other than that, there is really nothing you can do with a high FICO score."

In fact, he says, a good FICO score often leads to a bad FICO score, because people are able to take advantage, and often do, of unnecessary credit that ultimately leads to more debt.

One prime example is a car loan, which he says you should never take out in the first place. "The best thing people can do for their lives, in terms of happiness, is to avoid monthly payments entirely whenever possible," he says.

Forget New, Buy Used

Buying a used car these days not mean driving a vehicle with 100,000 miles and severe maintenance issues, Bissonnette says. Used cars are not only cheap but safe drive too. His suggestion is to buy a used car for just a couple thousand dollars. Not only will your bottom line not suffer from instant depreciation of the car the moment you drive it off the lot, you will also not likely need to buy collision insurance. You probably won't need theft insurance either, he says, because thieves are less likely to steal older cars.