The Canberra CEO and founder of custom sportswear apparel provider, ONTHEGO promised himself he would write his first book by the time he turned 30. At only 28, he's done that easily.

Spencer has expanded ONTHEGO over the last six years from his parent’s garage to a global e-commerce company that designs and manufactures custom sports apparel and accessories.

But the former Daramalan College student was always entrepreneurial, hence the car washing and later a whole host of after-school jobs and on-the-side projects including attending garage sales as a teenager and re-selling his finds on eBay.

"One time, a professional basketballer, Lauren Jackson (of Olympic, WNBL, WNBA and WBC fame), gave me $20 to wash the windows of her Mercedes, and when other people coming out of the shops saw this, they of course also wanted their car windows washed by … yours truly,'' Spencer writes.

"Lauren became a weekly customer and the power of her influence taught me that if you’re endorsed by someone who is well known and respected, you can capture a lot of sales.''

Spencer always did it his way, not following the rules and always wanting to disrupt the status quo. He did it tough as a youngster, born almost blind and later suffering dyslexia and ADHD. He was also later diagnosed with two serious heart conditions.

One of the heartbreaking sections of the book details his daily run-ins with bullies at school where he was called "four-eyes fatty'' and abused every day on the bus, "occasionally bursting into tears once I was home''.

By the age of 12, Spencer was too scared to leave the house on weekends. His parents Greg, a builder, and Cathy, a nurse, refused to mollycoddle him. One Saturday, they gave their son $50, told him to get on a bus, "go to new places'' and use the money "to explore and discover''.

"I didn’t even have a mobile! I was scared, of course, and didn’t want to go. ‘You’re going,’ Dad said, ‘and I don’t want to see you back here until after 5pm tonight','' he writes in the book.

It was a turning point.

"Even though I felt scared, there was something else — it was thrilling! I loved it! That day is responsible for my constant addiction to adventure, to finding new things and to operating outside of my comfort zone.''

Spencer’s book is a mix of autobiography, tips for overcoming adversity, personal anecdotes, and advice he has learned along the way from billionaires, global CEO’s and highly sought after founders.

He says he was inspired by the naysayers, teachers and bullies "for their constant reinforcement that I was not worthy of success because I was so different''.

"A lot of the book is about motivating that younger generation that anything is possible, no matter what happens,'' he said.

"But also for adults, looking at any problems we do have in our lives as an opportunity to grow from that.''

Spencer goes into more details, too, about that whole Shark Tank chapter when, in 2016, his then fledging company was offered a $600,000 investment from three sharks in return for a 30 per cent stake in the enterprise.

He accepted their offer but then, during the due diligence process, ended up refusing the investment, not least because the sharks couldn't commit to advising him one day a month for a year.

"I had to think further than the money at hand,'' he said. "I felt the pressure they put on the business, it was not going to be worth it.''

Spencer says writing the book over two years was "very emotional''.

"I think it was one of the first times in building OTG that I actually reflected back on who I've met, what I've learnt,'' he said.

"How did I end up meeting Richard Branson? How did I end up having a beer with Bob Hawke and Steve Waugh at the cricket? I'm just one of those people who get bored quickly and don't celebrate the successes as often as I should and this whole thing has just been very exciting.''