Wollongong designer and artist Simon Grant says it can be a hard sell trying to convince someone to allow you to paint an enormous graffiti artwork on their business' wall.

He runs the up-coming three-day Wonder Walls Festival in Wollongong - a growing event now in its second year that sees major professional graffiti art created throughout the CBD.

"I can see why they're apprehensive because you have a random guy lobbing up in the street asking if he can paint this thing on the side of your building," he says.

"The property owners are amazing though - they don't see any design briefs or proofs, they just trust us to turn up and make their wall look beautiful."

And if you were a business that turned down his invitation last year, you'll probably be kicking yourself now.

Last year's major work - an enormous and beautifully created girl's face painted on a wall on Keira Street by artist Rone - has been unanimously acclaimed.

"The thing last year was nobody knew what the girl's face was a part of, but this year people are more aware of the event.

"It's [the girl's face] what got people last year - the Wollongong public didn't know it was coming and it just popped up."

And this year, he's wanting to go bigger, and more of it.

While he can't reveal what will be painted, the organisers have come to an agreement with the Wollongong Central GPT group and Wollongong Council for renowned graffiti artist (and ex-local turned Glaswegian) Smug to work on a major project.

"A lot of people are surprised with how this stuff [artwork] starts and how it's planned, so it's a good chance for people to check it out and if they are fans of the artist, they can say g'day and see what goes into the work," Simon says.

The festival is a collaboration between him and Sydney-based group The Hours, and will feature a three day program starting with the opening in Globe Lane in Wollongong's CBD this Friday 8th, and carrying through until Sunday 10th.

"Last year was to get some runs on the board and it started modestly - it was us finding our feet and making sure the format could work, but it was always our idea to build it."

He says the graffiti art scene in Wollongong has been strong for years.

"There are guys who were painting in Wollongong in the early 90s, so there's always been a scene, but it's a way to not necessarily formalise it, but shine a light on it.

"There are a tonne of talented artists down here."

The festival also serves to help promote quality street art and perhaps open people's minds to the art form.

While 'tagging' vandalism continues to be a problem in all cities, Simon says the festival helps the public separate the thoughtless graffiti from the technical art.

"There's an emphasis on creativity with everything we do, and you'll always get haters, but we do our best to keep graffiti positive.

"I'm always thinking, and I've always got my eye on walls - we're always looking for new spots and bigger spots."