While chief executives around the country prepare to sleep rough for charity, a group of fashion lovers have been rummaging around Canberra for sartorial diamonds in the rough to star in a fashion show with a twist.

High-vis vests, a camouflage bum-bag, retro leather jackets and a wedding dress with more ruffles than the inner circle of the ALP will be among some of the looks showcased at the second annual Help from the Underground show on Wednesday night.

The fashion show fundraiser will once again feature nothing but recycled clothing and accessories sourced from St Vincent de Paul.

Last year, the first event raised $18,000 for the ACT arm of the charity and, according to founding director Clinton Hutchinson, the stage is set for an even bigger and bolder show.

''All of the outfits come from local St Vinnies stores, are styled by local designers and all the money then goes back into the Canberra community via all the St Vincent de Paul branches,'' Mr Hutchinson said.

''There is some out-there stuff which will be coming down the catwalk this year which is pretty wow, we're really pushing it this time, these designers and the entire production team have taken creativity to the next level.''

Help from the Underground will once again take over the Zoo Advertising car park with a runway, pop-up store selling vintage and quirky looks curated by local bloggers and a soup kitchen. Mr Hutchinson and the team, who also worked on the first Fashfest event in May, are hoping to raise as much as possible to help Canberra's most disadvantaged people.

Producer Steven Wright, a senior lecturer in fashion at the Canberra Institute of Technology, has been working with the eight labels who will be showcasing.

''The designers had a brief when they were given full access to the huge St Vincent de Paul warehouse,'' Mr Wright said. ''With their six looks, they must show off their design philosophy using the best op shop treasures they could find.''

He said the day the designers pulled looks for the show was like a real-life episode of Project Runway due to the mayhem and endless opportunities inside the charity's stores. As well as five individual outfits, each designer will present a ''blue look'' as an homage to the St Vincent de Paul Blue Door Drop-in Centre.

Admission to the event is ''free, but generous donations are encouraged''.

■ For more information and to RSVP head to www.helpfromtheunderground.com.au.