When Darren Cullen otherwise known as Ser was expelled from a school in Croydon, he went to work with his dad in the family business, writes Dean Piper.

But Darren knew he was not happy with his life.

With a couple of City and Guilds qualifications, he had little idea what to do with his future.

Darren turned to graffiti to fill any spare time, writing his graffiti signature, or tag, everywhere he could.

He told me: "All I would do in my spare time was graffiti all around Croydon. It was just tagging and vandalism, but I needed to do it, I was under so much peer pressure to carry on spreading my tag.

"Back then my tag was Hassle. It would be everywhere, all over the place. I don't really know why I continued to do it. You would always get into big trouble if you were caught."

Darren, now 28, was in fact caught by police at the age of 16. He was grounded for six months by his parents and wasn't allowed to go out anywhere after finishing work with his Dad.

"They were very upset about me being caught vandalising the local area. But they didn't realise how much I had actually tagged. I practically covered areas with graffiti."

The long six months ahead would force Darren to think about what to do to occupy himself.

He started researching comic books and practiced drawing his favourite characters. Eventually he became an expert at sketching his own cartoon visions in free hand and realised he had a real skill.

"I was still trying to get out of being grounded but at the end of the day my parents were just very ashamed of me. I only got into graffiti originally as it was the in thing to do. Then I realised it could be an art form."

Within weeks after being released from home, Darren went to an abandoned train line shelter in Croydon to perfect his artistic talent. After practising over and over again, he was feeling confident he could market his work into something positive.

Seven years ago Darren started working professionally as a graffiti artist. He has sprayed murals, shop fronts, school walls and private walls and has now become a successful businessman in his own right.

But Darren's talents went even further when he was asked by Merton Council to open a graffiti workshop for young vandals to control their illegal habits by spraying on designated walls.

"From the workshop, it got to the case where councillors from other boroughs had heard what was going on in Merton and wanted me to set one up in their borough.

"We were asked to paint the train station in Wallington and at that point there were over 50 kids in the project and about 300 turned up to see what we were doing."

After two and a half years at the project, Darren left to continue his own business ventures.

Summing up his time at the project, Darren said: " I used to ask the kids why they did graffiti, to try and understand them.

"Some were just into the vandalising side of it, others did it because everybody else did it, but none of the kids really talked about the artistic side of things.

"No matter what, I have certainly made hundreds of kids stop doing graffiti illegally.

"The way to stop kids tagging illegally is to have an ongoing campaign running in the local area. Without that, the kids will continue to cause havoc for the neighbourhood. It's just not enough to start a campaign or youth group and stop after two months. These schemes fail every time."

Darren has been a vandal, an artist and a youth worker and has seen all sides of the graffiti spectrum.

He is a living example of how to turn something that once plagued the community into something which can benefit it.

q Next week we will be speaking to the people who are responsible for washing off graffiti from walls and we will look into the cost of cleaning up our borough.