When you're first thinking through an idea, it's important not to get bogged down in complexity. Thinking simply and clearly is hard to do.

We have a business that some people feel pollutes, and I happen to agree with them. ... And so on the basis of trying to do good and, you know, hopefully turn a profit, what we did was we pledged that we'd put all the profits from our airline business into trying to develop clean fuels.

And in the process, we have come up with fuels - algae-based fuels, isobutanol-based fuels and other fuels - that we think will power the planes in the future so that, you know, by 2020 I hope that our planes will be powered on fuels that are clean fuels and are not polluting the environment so that we'll have a green airline and an airline that actually has fuels that will be hopefully cheaper than the dirty fuels of the past. So [we're] doing good and also turning a profit at the same time.

The balloons only have one life and the only way of finding out whether they work is to attempt to fly around the world.

I doubt that I would have been successful in my career and happy in my personal life if I hadn't prioritized health and fitness. Staying active ensures mental preparedness and the courage to try new things. It helped me to stay focused on work but also to have fun and try new approaches and explore new places. That's the spirit behind Virgin Sport - we wanted to introduce fitness activities that are enjoyable, accessible and part of your overall lifestyle.

My mother was determined to make us independent. When I was four years old, she stopped the car a few miles from our house and made me find my own way home across the fields. I got hopelessly lost.

When you are ready to make your first hires, look for people who understand your passion, want to add to your ideas and can envision ways to make improvements.