I was handed a six-year prison sentence at the age of 23. I’d left school in Bradford at 15 with no GCSEs. I had always been a visual learner, and liked making things with my hands, so I trained to be a mechanic. My intentions were good, but I was only on £20 a week. Even alongside a training allowance of about £60, that wasn’t enough to live on; within a couple of years, I’d fallen in with a bad crowd and crime became my sole source of income.

I spent the middle part of my 20s inside, serving a total of four years. In 2007, I was granted release on temporary licence. With the prison’s phonebook and computer, I wrote more than 100 letters asking employers across the country for unpaid work. I wanted to be proactive, but received only three replies – all rejections. Eventually, Seagulls Reuse in Leeds took me on as a volunteer. It is an environmental social enterprise that rescues 400 tonnes of paint from landfill annually and repurposes it to offer a bespoke paint-mixing service. I carved out my own role, mixing paint, working with other volunteers and assisting customers, before being hired as a decorator and fully fledged member of staff.

I was so used to people saying, “I’ll do this for you, but I want this back in return”, but the staff had no agenda or ulterior motive. Even so, it took some time to break down the hard exterior I’d built in prison. My manner with customers needed work, and I sometimes got into arguments with my bosses. They’d scold me for making the wrong colour, or putting paint pots on the wrong shelves. I once had an argument about a cream pot that they kept telling me was green. It wasn’t until then, in my late 20s, that I realised I am colour-blind.

Mixing paint is nothing like the colour wheel you learn at school; blue and green doesn’t just make green. You don’t even mix different greens to make green paint. It’s more technical and complex than that, and there are so many subtle variations. You have your strong base colours: black, violet, magenta, blue, red, yellow and brown. Then you mix in more paint, or pigments, with a spatula and paddle drill. Yellow is for brightness, red a diffuser, and brown, black and violet create depth. So, to get Hague Blue, for example, you mix black and blue, but also add violet. It might seem illogical to add purple, but you need that to bring out the blue.

Dulux and other big companies let machines do all the work, but our process is nothing like that. We can also only use the colours we have in the warehouse that day, so we sometimes have to get creative. They have scientists, but we have our intuition, years of experience and an essential human touch – and eye.

I’m 38 now, and have been at Seagulls for 11 years. I’ve learned that I struggle most with earthy tones. I see green in dark browns and creams. Some reds I see as pink, and with light pink, I see a minty-green. So, along with the knowledge I’ve now memorised, I use different tactics with customers. I get them involved by explaining how I’m creating their paint and encourage feedback. That way, we’re both helping each other get the perfect result. I also learn from my mistakes, and log things I do wrong, so I don’t repeat them.

If I tell customers I’m colour-blind, they’re always shocked and say they’d never have guessed. That said, everyone has a different perception of colour and I’m sure I’ve had colour-blind customers in the past.

One of my responsibilities is training new volunteers, so I also work with a lot of ex-prisoners. Sometimes they tell me I don’t know what they’ve been through, and it’s always useful to let them know that, actually, I do. When they hear my story, their whole demeanour changes. Their struggles may be different from my background and colour-blindness, but I can still empathise and show them that I overcame it and adapted. I do have a visual impairment, but I don’t resent it and wouldn’t change it even if I could. It’s made me push myself harder.

I still live in Bradford, though working in Leeds has helped keep me away from my old life. I don’t want to make excuses, but I made bad decisions out of desperation and a lack of opportunities. I want to pass the support I’ve been given on to others who need it, and to see the business grow. We offer a far superior service. We’re not second fiddle to the big boys.

• As told to Grace Holliday

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