Zac Posen thinks confidence is key on the red carpet.

The designer has dressed the likes of Gwyneth Paltrow and Eva Longoria for high profile events in the past, and says the most important thing his clients need to pull off a show-stopping look is a sense of humour and a positive attitude.

Asked what the red carpet is all about, Zac replied: ''Having fun ... Feeling comfortable and feeling that 'wow'. You have to have that confidence - it's the most important thing.''

The fashion maven is known for his strong and feminine designs, and believes it's important to empower his customers by making them feel glamorous and womanly.

Zac explained: ''Glamour is a celebration of feminity. I like the magic moments in life. I like celebrating femininity and beauty - it's about seduction.''

The 'Project Runway' judge credits 'Black Swan' actress Natalie Portman with helping him become a household name when she wore his black-and-white gown to the 'Star Wars Episode II: Attack of the Clones' premiere in 2002.

Quizzed about his favourite red carpet moments, he added in an interview with ''When I was just a kid and starting out and doing my first red carpets, those moments with Natalie Portman were magic!''