The last few weeks of the year can be equal parts profitable and stressful for a small business. Anyone who has fought their way through a Black Friday madhouse or a mall-traffic nightmare knows how frustrating things can get — and that’s just on the shopping end of the spectrum.

That brings us to an idea that is always worth discussing — the need to stay positive. For small business owners, it is essential. Not only will it rub off on employees, but it can have a positive effect on customers as well.

Here are a few ways to look on the bright side of life.

Avoid being “mean” — Sounds obvious, sure. But take a recent essay titled simply “Mean people fail” by Paul Graham, co-founder of Y Combinator, which provides seed funding for startups. In it, he describes how few successful people he knows would qualify as “mean” (and acknowledges that he may have “selection bias” in his circle of “startup founders, programmers, professors”). Graham explores the idea that “being mean makes you stupid,” especially in conflict. “That’s why I hate fights,” he says. “You never do your best work in a fight, because fights are not sufficiently general. Winning is always a function of the situation and the people involved. You don’t win fights by thinking of big ideas, but by thinking of tricks that work in one particular case. And yet fighting is just as much work as thinking about real problems. Which is particularly painful to someone who cares how their brain is used: your brain goes fast but you get nowhere, like a car spinning its wheels. Startups don’t win by attacking. They win by transcending. There are exceptions of course, but usually the way to win is to race ahead, not to stop and fight.”

Skip the me-first approach — A selfish attitude can damage hopes of a successful startup, including the “I’ll do what I want” way of thinking. Lyve Alexis Pleshette of calls this “anti-customer thinking that should be purged from the minds of every entrepreneur. You put your needs first instead of finding out what your customers want. You operate your business in a way that is convenient for you. Sure, you are the lord and master of your own business. After all, this business started with your blood, sweat and tears. However, your business is not about your ego. Customers do not patronize your business to pay homage to you and what you have produced and accomplished. Rather, they buy your products or service because you provide for their needs.”

Good attracts good — A key element for many small businesses is bringing top talent into the fold. And that may be hard to do if the leader doesn’t have a positive presence. In Graham’s “Mean people fail” essay, he describes why these entrepreneurs can miss out. “They can hire people who will put up with them because they need a job,” he writes. “But the best people have other options. A mean person can’t convince the best people to work for him unless he is super convincing. And while having the best people helps any organization, it’s critical for startups.”

Stay flexible — As stress levels increase — as they often do toward the end of the year — stay focused on the ability to shift and adjust. Bob Reiss calls flexibility a key attribute to put you “in the right mindset for achieving entrepreneurial success” in a piece for “It’s a given that your plans and strategies will change as time goes on,” he says. “This flexibility for rapid change is an inherent advantage of small over large business. However, no matter the pressure for immediate profits, do not compromise on core values.”