Until 2016, I ran an advertising agency in London. At our peak, we were highly successful; I had a team of 35 people, a £3m turnover and a Covent Garden office. When the agency folded, I decided to invest in bitcoin.

Bitcoin is a cryptocurrency, a type of electronic cash that allows people to spend or trade via a peer-to-peer network without the involvement of banks or other intermediaries. It is a cheap, efficient way of transferring funds or holding value, which can be converted back into sterling at any time. I had used it before to buy treatment online for my mother after she was diagnosed with cancer. I had also dabbled with investing in it in 2013, and made and lost some money: bitcoin is prone to sudden fluctuations in value. But the market seemed to have moved on, and I decided it could be a good way to make some profit on my savings.

At first I deposited £5,000; at the time, January 2017, bitcoins were about $600, so I bought seven or eight and spent the rest on other cryptocurrencies. But over the next few weeks I became hooked and ploughed in a large chunk of money – £23,000 in all. I remember telling people, “I really think the value of bitcoin could rise to $2,000 this year.” I could never have predicted it would peak at 10 times that. By the middle of spring 2017, my investment had risen to about $300,000, and by the summer it was at half a million. Media interest in bitcoin was growing and friends kept asking how they could get into it, so I started a Facebook group, then a website and finally a podcast devoted to the subject. As excitement built, more and more people got involved, forming the conditions for a bubble; but many of us were too caught up in the hype to exercise caution.

At the end of 2017, bitcoin had reached almost $20,000 and my portfolio had ballooned to about $1.2m. That is when I got a little out of control. I have always been an entrepreneur, and since I was a kid I had dreamed of buying my local football club, Bedford Town, becoming chairman and getting them into the league. I thought the project might cost £5m, so that was the figure I decided to aim for. I estimated I could get there within six months.

By this time I was travelling the world doing interviews for my podcast, taking friends out to expensive restaurants and buying extravagant gifts for my family. I am not the kind of person who puts everything away for the future, and though I donated £6,000 to my local hospital, much of my spending was quite frivolous. It might have been more sensible to buy a couple of houses, but I became overambitious. This felt like my one shot at achieving that childhood dream.

At the end of January 2018 the bubble burst and bitcoin’s value suddenly fell. There had been a few drops during 2017 but it had bounced back, so I was not too worried. But over the rest of the year, I watched it sink lower and lower, along with the other cryptocurrencies I had invested in, all the time thinking, “Well, there’s no point selling now…” That was my attitude throughout last year, as bitcoin’s value continued to fall. Pretty much everything I had built up was wiped out.

There are many who invested a lot more than I did and ended up with far greater losses. I wish I had taken everything out before the bubble burst, but I do not waste too much time on regret. I have earned money in the past through hard work and enjoyed it more. At the moment, I am enjoying making my podcast, which provides more than enough money to live on. I have sold most of my bitcoin, which is currently worth about $4,000 apiece, to give me a cushion in case the business has a bad month. But if I had to choose between the $1.2m and the podcast, I would let the money go again – I love what I do now.

I still believe that bitcoin is a force for good. I recently interviewed Alex Gladstein of the Human Rights Foundation, who was explaining how it helps people living in authoritarian regimes to prosper – for example, women in Afghanistan who are not allowed to open bank accounts can still work and get paid in bitcoin. It is a step in the right direction. My main focus now is exploring how bitcoin could help stabilise an increasingly volatile world.

As told to Chris Broughton

• The headline of this article was amended on 11 January 2019, for clarity.

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