London, England (CNN) -- Spring is in the air and with a royal wedding afoot, what will the best-dressed guests be wearing at Westminster Abbey on April 29 when the UK's Prince William marries Kate Middleton?
This season's hot catwalk trends should hold some clues: Major looks from the Spring/Summer 2011 shows include bright block colors, florals, lace, prints and long lengths, as seen at designers including Jil Sander, Prada and Marc Jacobs.
But while the fashion pack might favor avant-garde looks, when it comes to spring wedding dressing -- and particularly dressing for a formal occasion like the royal wedding -- some looks will work better than others.
"Think dresses, think long, flowing beautiful dresses," says Rose Easton, a fashion buyer for the Shop at Bluebird. This smart London shop can be found on the King's Road, one of bride-to-be Kate Middleton's favorite places to shop.
Ruth Runberg, the buying director at upscale London fashion retailer, Browns, agrees -- and what's more, she says that the maxi look could work for other occasions too.
"We're really excited about the new, longer length. It would be a great investment piece, so grab a maxi dress or skirt for spring and it's something you could definitely carry through into the fall season," she says.
What's more, fashion-forward wedding dressing doesn't have to be reserved for those lucky royal wedding invitees. Dresses are versatile and don't have to be expensive.
"It's a great season for dressing up for a wedding," said Bloomingdale's fashion director Stephanie Solomon. "You can wear the same dress to the beach, because believe it or not, the maxi dress is back in full swing and those longer lengths are appropriate for wearing over your swimsuit and to a wedding," she continued.
Those on a lower budget needn't worry, though. That 70s look, which was on show at Marc Jacobs and at Gucci, Runberg said, "is everywhere, at every price point."
Sheer, floaty chiffon will be a sure-fire summer staple, says Chloe Weguelin, a spokesperson for London department store Liberty, but wedding guests needn't shy away from bright colors.
Mosha Lundstrum Halbert, fashion news editor for Canadian fashion magazine Flare, says that we can expect to see a lot of "great pops of color, from orange to Wedgewood blue" this summer.
As for the royal wedding, some things don't change with the whim of fashion and because of this, Halbert expects to see "a lot of hats and fascinators, as this is a British wedding.
"But also a lot of exuberance, (people) are really excited about this wedding and they're probably going to express that in their dress sense -- again lots of color, lots of vivacious prints."
It's one thing to advise on the latest trends, but how would a fashion professional tread the line between traditional and on-trend if they were invited?
Runberg says she would opt for something in her favorite color, pink, but would insist on keeping things "appropriate" for the occasion.
Halbert would choose a dress by Canadian-born designer Erdem, because "the spirit of his clothes -- and the mixed florals that are at once super classic but modern and timeless -- would be perfect for the royal wedding."
London-based designer Silvina Maestro says that she would wear a design by the late UK designer Alexander McQueen, while London stylist Kit Lee says she would wear a classic Burberry trench, but floor-length in homage to the summer maxi trend.
Not all would so discreet. Rose Easton from the Shop at Bluebird said: "For the wedding? Something see-through and black, and be told off and thrown out!"