Constructing the perfect ensemble--whether it's for a fancy evening fete or something suitable for a day of appointments--is something we think about constantly. After considering a variety of important factors (like silhouette, colour, accessories, and comfort), we hunt down the best pieces in our closet and try to put them together into one cohesive look--a process that is sometimes much easier said than done! Of course there's always a much simpler method than this trial-and-error process: you can just tune into our latest instalment of What Was She Wearing: Answers. With all the need-to-know facts about your favourite celeb outfits--like Diane Kruger's gorgeous lace frock and Kate Bosworth's cool grey mix--and advice on how you can achieve likeminded looks, you've got everything you need right in front of you. If only everything was this easy...

1. Kate Bosworth
Kate Bosworth's style is the epitome of laidback California luxe. Her outfits are always effortless and stylish, and today's featured look is no exception. You spotted the trendsetter at a party for The King's Speech at the Chateau Marmont two weeks ago wearing a grey Isabel Marant dress from the F/W 10 collection and a pair of taupe boots, also by the French designer. She finished her look with a mix of gold and silver necklaces from JewelMint, her online-only jewellery collection, and of course, her trademark blonde locks. Bosworth clearly has a knack for mixing neutrals, so we've tracked down some affordable and in-stock pieces to help you achieve her look! First, pick up Forever 21's Basic Long Sleeve Top ($10) in Grey and pair it with Topshop's Print Drape Wrap Skirt ($55). Next, you'll want to grab Sam Edelman's Farell Ankle Boots ($70) in After Dark--they are an excellent alternative to her amazing Isabel Marant pair--and then simply accessorize with Elle's Purple Jasper Oval Drop Pendant ($90) to complete your Bosworth-inspired ensemble.

2. Olivia Palermo
Finding noteworthy outfits on Olivia Palermo is never a difficult task for your Who What Wear editors, but it's been particularly easy lately, thanks to fashion-show season! Of all her amazing ensembles recently, you were particularly fond of the look she put together for the Mulberry F/W 11 show. Incorporating plenty of cosy layers, Palermo wore a DVF shirt with a number of Mulberry pieces, specifically the Tippi Jacket in Waders Green, Polly Push Lock Sheepskin Duffle Coat, and Culottes in Fox Tweed--all covetable items from the F/W 11 collection. She finished her outfit with two standout accessories: a pair of violet suede Giuseppe Zanotti oxford booties and Mulberry's Oversized Tillie Bag ($3000) in Bengal Tiger. If you want to construct a similar outfit for yourself, we suggest starting with Madewell's Liverpool Cropped Trench Coat ($158) and layering it under ASOS'Cotton Hooded Cape Trench Coat ($100). For the rest of your outfit, try ASOS' Premium Tailored Pleat Culottes ($72) and Me Too's Lisbon 14 Oxfords ($104), and you've got yourself a prime between-seasons look.

3. Hailee Steinfeld
Aside from being too adorable for words and a seriously talented young actress, Hailee Steinfeld consistently gets it right with her ensembles--something we are always excited to see! And based on all the inquiries that have come pouring in over the few weeks, you also approve of her age-appropriate and fashion-forward dressing, especially the Valentino Technocouture Dress ($2490, 212.772.6969) and Aldo Hoxworth Pumps ($60) she wore to the Finch and Partners Pre-Bafta Party in London last week. An exaggerated shoulder, like her frock's white rosette detailing, adds visual intrigue to a simple silhouette. And while Steinfeld's exact Valentino pick is investment-worthy, we think Quontum's One Shoulder Dress ($110) and A Wear's Sculptured Sleeve Dress ($63) are both spot-on, affordable alternatives worth checking out.

4. Ally Hilfiger
Wearing a burnt-orange dress with turquoise platforms and fishnet tights is certainly no easy feat to pull off, but Ally Hilfiger did so with aplomb. Earlier this month, the stylish New Yorker appeared at the pre-opening party and shopping event for DRESSED--a documentary that chronicles the compelling story of designer Nary Manivong and his journey from homelessness to New York Fashion Week--in a one-of-a-kind dress by the film's subject, paired with Prada's Platform Sandals ($795). We appreciate Hilfiger's bold colour combo, and because we know you're smitten with the daring ensemble as well, we've rounded up some similar items to help you recreate the look! We think Diane von Furstenberg's Bairly Louche Silk Dress ($325), which shares a similarly stunning orange hue, would look perfect with Steve Madden's Vanissa T-Strap Pumps ($70) in Blue Suede. Try this look for your next festive cocktail fete and we promise all eyes will be on you.

5. Diane Kruger
Diane Kruger never fails to impress with her winning ensembles--especially her awe-inspiring dress choices. The actress looked ravishing in a lace dress from No. 21's Pre-Fall 2011 collection (which is designed by Alessandro Dell' Acqua) and nude Brian Atwood Maniac Pumps ($580) to a party celebrating her March cover for Glamour magazine earlier this month. The look is certainly sweet and memorable thanks to the frock's pretty lemon sorbet hue, intriguing draping detail, and delicate ruffles. To achieve Kruger's precious look, we suggest picking up Pins and Needles' Lace Dress ($69), A Wear's Lace Tier Side Dress ($72), or Sandro's Reminence Lace Mini Dress ($390); any of these options would look great teamed up with Vince Camuto's Kain Heels ($79) for your next cocktail party.--Jessica Baker, with additional reporting by Erin Fitzpatrick

Photo of Kate Bosworth, courtesy of Getty; Photo of Hailee Steinfeld, courtesy of Splash; Photo of Olivia Palermo, courtesy of PCN