"There's no guidelines here," said graffiti artist Darren Wolfe as he stood atop a scaffold Saturday morning behind White Buffalo Youth Lodge.

"It's run what you brung*. Pick whatever you want to paint, whether it's letters, a skull or a character."

Artists worked from scaffolds rising about halfway up the wall. (Guy Quenneville/CBC News)

Wolfe — teal spray paint can in hand — was one of 29 artists painting the entire back wall of the 20th Street youth centre with a panoply of variously-coloured designs.

By invitation, of course.

"I'm 36 years old and I'm too old to run from the police and so I don't paint anything illegal," said Wolfe.

Artist Darren Wolfe said he's too old now to run from the police, which is why he was taking part in Saturday's sanctioned event. (Guy Quenneville/CBC News)

Artists from Vancouver to Winnipeg — and even one from Los Angeles — were taking part in the 11th Saskatoon graffiti event Saturday, which was expected stretch into late afternoon.

More than one artist preferred not be interviewed, or even photographed, preferring to remain in obscurity.

Not so with Wolfe.

"It started out through my love of art and wanting to put my name in as many places as I possibly can," he said of his start in graffiti.

WATCH: <a href="https://twitter.com/hashtag/saskatoon?src=hash">#saskatoon</a> <a href="https://twitter.com/hashtag/graffiti?src=hash">#graffiti</a> artist Darren Wolfe on the current graffiti scene and why kids need to "step their game up" - legally <a href="https://twitter.com/hashtag/yxe?src=hash">#yxe</a> <a href="https://t.co/L1HaOlB3K5">pic.twitter.com/L1HaOlB3K5</a> —@gq_in_sk

"Basically I wanted people to pay attention to me, I suppose, and I wanted to grab their attention in the right way, by showing them what I can do with a spray paint can."

A group of onlookers watched the artists-on-scaffolds intently.

The painters and their audience. <a href="https://twitter.com/hashtag/yxe?src=hash">#yxe</a> <a href="https://twitter.com/hashtag/saskatoon?src=hash">#saskatoon</a> <a href="https://t.co/Cs7gzYnyb8">pic.twitter.com/Cs7gzYnyb8</a> —@gq_in_sk

Co-organizer Mark Charmbury manned the table where a deep (and colour-coded) supply of spray paint cans awaited participants.

The cans at artists' disposal. (Guy Quenneville/CBC News)

"It's just an opportunity for a bunch of writers to get together and create and express themselves and their various styles," said Charmbury.

This year's event even spread to a wall on the nearby City Centre Church.

"It's allowed for the artists to go bigger with their pieces. We don't have to squish everyone in, which is kinda nice. It just gives more art for the community."

The event will be capped Saturday at 9 p.m. with a screening at The Broadway Theatre of "Can't Be Stopped," a documentary about the influential C.B.S. graffiti crew from Hollywood.

* According to Urban Dictionary, "run what you brung" is "a term used for street races, where you accept the results of a race instead of making theories how the race could have turned out differently."