But his Wild West charm stood in stark contrast to the other, more traditionally eclectic, troupe of performers hanging around the impromptu campsite in their exotic costumes.

Trapeze artists in spangly Lycra chatted in a maudlin Eastern European tongue through mouthfuls of cigarette smoke.

While a clown dressed as Uncle Sam sat on the coupling of a caravan, nervously playing with his stars-and-stripes-clad top hat.

"I have to speak half-a-dozen languages to be able to talk to all my performers," Gavin explained. "They come from all over the world, these guys.

"But, after 55 years in the profession - travelling around the world with various circuses - I've picked up most languages."

"Buenos tardes!" he announced, as if to prove the point, as he stepped into the clown's caravan and exchanged a quick conversation in Spanish with Ramon and Martha Martinez.

Both Ramon and Martha are clowns.

And it looked increasingly likely that I would be joining them with the custard pies in this evening's production.

With a Jimmy Durante lilt, Gavin shook my hand: "Good luck son, you're gonna be a clown. See you in the ring."

Inside the caravan, Ramon quickly sat me down and got to work with his make-up brush on my face.

The 45-year-old funnyman was already made-up, and his painted on smile betrayed the concentrated frown as he artistically drew out my mask.

"I come from Colombia," he told me. "I started working as a clown in Mexico 20 years ago - it was just a way of finding work.

"It's not a bad life, really," he said. "The thing about clowning is that it's a very visual comedy - so it's understood by people everywhere.

"My English is not so good, but it doesn't need to be with visual comedy."

Although Ramon's experience of clowning around the world - from South America to India - has led to some differing routines.

"What people find funny in one country can be a little different to another - but it's always pretty much the same.

"In Mexico, for example, they like more play fighting, while in Europe they just like you to look silly - dancing about with big feet."

Suddenly the glamour of circus life began to drain from my imagination.

"Stand up," Ramon said, before surveying me up and down quizzically.

Ramon was a little shorter than Gavin, and the thought of squeezing my six-foot body into one of his spare clown costumes was already troubling me.

But he seemed quite comfortable with the proportions as he turned to his wardrobe and took out a pair of billowy tartan trousers, a matching tartan waistcoat and a flowery shirt.

I stepped into a back room, removed my suit, like the 1970s cartoon character Mr Benn, and as if by magic, stepped out looking appropriately silly.

"No, you must be smarter," Ramon said with a wry grin, as he handed me a large pink comedy tie.

The size differential came into play a little - Ramon's trousers had become breeches on me. So to cover up my hairy calves, Ramon produced a pair of fluorescent pink leg warmers.

"I think my feet may be a little bigger than yours," I suggested.

"No problem," Ramon said, reaching into the base of the cupboard, "We specialise in big shoes."

The pair he handed me were true clown boots - beaming out bulbously at the end.

"Now all you need is a nose," he added, as he placed a sequinned cap on my head.

He pulled out a box of red noses - scores of them, in varying shapes and sizes. He held one up at arm's length, closed one eye, like a painter working out proportions, and shook his head.

He pulled out a slightly bigger one, and tried it again. It too apparently was not of ample size.

Eventually he found one big enough to take on my nasal protuberance, and rammed it on my face with some force.

So, we were ready.

Without a hint of mirth we walked together across the rec' towards the big top.

Once inside the massive tent we headed into the back stage area, where Ramon was still clearly seething about the cheeky youngster beneath his painted-on smile.

Gavin shook my hand again, and offered me a final piece of advice: "You've got two expressions to remember - happy and sad."

With that he disappeared behind the curtain to an excited round of applause from tiny hands.

As the show started, the famous circus anthem kicked into life. Ramon leaned against his full-sized clown car and got into a heated debate with one of the trapeze artists about the cheeky child.

The music flowing through the curtain was punctuated by the occasional burst of laughter and sharp intake of breath from the audience.

Ramon's argument with the Celebrated Mr Kite-type figure was reaching a climax, and I began to feel a little cheated of rehearsal time.

Perhaps sensing this, Ramon broke off and joined me.

"Follow me, and try to keep up," he suggested, as the Uncle Sam clown joined us, holding a ghetto-blaster.

With that the curtains opened, and we were on. Ramon skipped into the ring - suddenly the smiling playful character that you might expect from a clown. I stumbled after him, awkwardly tripping over my enormous shoes, and trying my best to look professional.

Following Ramon's lead I clapped along with the music, and danced around ludicrously.

Without my glasses - Ramon wouldn't allow me to cover up his work of art - I could barely see the audience. But they were about 250-strong - surrounding three sides of the ring.

Gavin appeared, and ordered the clowns to turn their music off. We protested extravagantly, and Gavin received a tirade of childish boos.

This routine was repeated on each side of the auditorium, to the sound of the children's laughter, before a group of dancers took our place in the ring, and we retreated backstage.

Ramon the Clown immediately transformed back into the rather more stern Ramon the Colombian.

But he shook my hand warmly: "A good job, my friend," he said, cracking his make-up with a smile. I returned to the clown's caravan holding my nose - my false nose that is - and reappeared, as if by magic, a few minutes later in my suit.

"I think that it's a great show," explained 38-year-old mum Sally Newman, as I crept into the front of the big top.

Sally had brought along her five-year-old son Joe.

"The clowns were my favourite," Joe said, smiling up at the strangely dishevelled man in a suit. "But the tall one wasn't very funny."