If mankind can successfully contain climate change, “[i]It will be the most amazing thing humanity has ever done, “said Bill Gates.

It’s going to take “an extensive effort, like a world war, but we’re against greenhouse gases,” Gates told Anderson Cooper on Sunday’s “60 Minutes” episode.

Gates is relentlessly optimistic. “There are days when it looks very difficult. If people think it’s easy, they’re wrong. If people think it’s impossible, they’re wrong,” he said.

“It can be overwhelming.”

If fighting climate change is overwhelming for billionaire philanthropist Gates, it certainly is for the average person. However, according to Gates, it’s important to remember that anyone can help.

“It’s easy to feel powerless in the face of a problem as big as climate change,” writes Gates in his new book “How to Avoid Climate Disaster”. “But you are not powerless. And you don’t have to be a politician or a philanthropist to make a difference. You have influence as a citizen, consumer and employee or employer.”

According to Gates, here’s what you can do to fight climate change.

Get political

Avoiding what Gates calls a “climate catastrophe” requires new power generation and supply systems that require “concerted policy action,” Gates writes.

“That is why participating in the political process is the single most important step that people from all walks of life can take,” he says.

Show your representatives that their constituents care about climate change by making phone calls, writing letters, and speaking in town halls.

“It may sound old-fashioned, but letters and phone calls to your elected officials can have real impact,” Gates writes.

Also, be informed and specific when dealing with politicians. For example, ask for funding for clean energy innovation research or a carbon tax and let politicians know your voice depends on their actions, he says.

Grassroots activism is important because electricity in particular is often regulated and regulated by national public utility commissions. Communicating with these officials can be an important lever for the average citizen to exert pressure.

Or if you’re that inspired, run for a local office, writes Gates.

Use your purchasing power

Buy and use sustainable products such as a smart thermostat that will help you regulate your energy consumption and the use of greenhouse gas emitting fuel sources. You can also vote with your wallet by, for example, signing up to get your energy from a clean source of energy and upgrading your old-fashioned lightbulbs.

“When you pay more for an electric car, a heat pump, or a plant-based burger, you’re saying, ‘There’s a market for this stuff. We’ll buy it,'” Gates wrote. And companies react to this information “pretty quickly in my experience,” he says.

Demand more from your workplace

“As an employee or a shareholder, you can urge your company to do its part,” Gates wrote.

While larger companies will have a greater impact on collective greenhouse gas reductions than smaller companies, smaller companies can come together in local organizations or chambers of commerce to achieve more measurable impact, says Gates. And bigger companies can work together to put pressure on even bigger suppliers.

Something like a tree planting program is an easy first step. And some companies have internal carbon taxes, Gates writes.

Talk to your family and friends