Join the boot camp: The ultimate guide to the season's hottest trend

Thigh-length, shoe-boots, waders – find the perfect pair and autumn dressing is a walk in the park. Carola Long introduces our definitive guide to a style that's got legs

According to the calendar it's August, but in fashion terms we're already in autumn. That means new trends, a new wardrobe and ... new boots. Schoolchildren might get excited about hunting for fresh, shiny conkers amidst the fallen leaves, but anyone with a passing interest in their wardrobe will get their thrills from a pair of fresh, shiny boots. However, this is no cheap, quick fashion fix. This is one purchase to be considered, evaluated, admired, desired. An investment. A "sole-mate".

Why? The right pair of boots accentuates the positive, creating an illusion of supermodel limbs. According to Manolo Blahnik, "It doesn't matter what sort [they are]; boots are boots. Some women are not born with beautiful legs or long limbs, but boots make your legs perfect. They are so sensuous, like a second skin." Just as Marilyn Monroe's 1950s swimsuits were far sexier than the near-nude dental floss swimwear beloved of Jordan, a covered-up leg is more exciting than bare knee and shin, however shapely.

Designer fashion also has a major crush on boots. The season's biggest trend is over-the-knee, and the look was so ubiquitous on catwalks that, as Vogue's executive fashion editor Calgary Avansino observes, "It was almost like a competition to see who could do the highest." And, perhaps, the most sexy. It's hard to imagine a more provocative item than Hussein Chalayan's long, black leather boots with built-in suspenders, or Gucci's Catwoman-style cuissardes. As Marc Jacobs says, boots that stop short of the tops of the thighs are "just very sexy".

The dominatrix style, erm, dominated the catwalks, but more left-field trends came courtesy of Miuccia Prada's green leather waders (think fetishistic fisherwoman) and Peter Jensen's joyful floral versions of native Greenlandic boots. And that's in addition to the other permutations that'll be stomping all over the high street: knee- or calf-high, ankle- or shoe-boots, flat, heeled or wedged; tassled, buckled, studded, metallic, carved – the list is as long as your leg.

Our love affair with boots has a long history. The Etruscans wore pairs with a turned-up toe; Beau Brummell kept his military-style boots shiny by polishing them with champagne. But, as a women's fashion item, they hit their stride in the 1960s. That's when over-the-knee boots became the perfect complement to the futuristic freedom of the mini-skirt. Mary Quant's plastic versions had a zip around the ankle so that they could be transformed into two styles. Towards the end of the 1960s a more bohemian, rock-groupie look had taken over – think of a louche Anita Pallenberg on her way to Tangiers in a tunic, feather boa and medieval-style boots; or YSL muse Betty Catroux getting married in 1968 in a black-and-white Pierre Cardin fur coat and patent-leather boots. That same year, Marianne Faithfull teamed her boots with head-to-toe leathers in the movie Girl on a Motorcycle, an outfit similar to Diana Rigg's Avengers costume.

Perhaps a clue to the enduring appeal of boots, then, is that they're are the female superhero's footwear of choice, thanks to their sleek suggestion of power. Catwoman's whip-cracking look would have fallen a bit flat if she'd teamed it with a pair of ballet pumps. High heels and a thigh-clasping tight fit aren't essential, though. A classic pair of masculine boots have a strong, sharp edge to them. When Mad Men's Betty Draper dons a pair of shiny chestnut riding-boots, her repressed 1950s housewife persona vanishes.

Boots are transformational. As Pam Brady, accessories buyer at Browns boutique in London, observes, "Boots give great attitude: they're tough, they're sexy – they are the easiest way to transform one's mood and height." With over-the-knee styles, however, there is a risk of looking less like Julia Roberts in Pretty Woman than a down-at-heel street-walker from The Bill. "[Tread] the fine line between stylish and slutty," advises Avansino, "by avoiding going too high and too tight. It looks better if the boots are a bit looser on the leg and come maybe inches above the knee." Her other tips are to opt for flat styles and wear them with something low-key. She says: "I like the flat boots as a day look."

For some easy rock'n'roll je ne sais quoi, the high-heeled ankle-boot is queen. Wear as high as you dare, and join the queue now. This season's most in-demand high-street boot – Pierre Hardy's chunky suede style for Gap – already has a waiting list of 80 people.

Peter Jensen: It takes courage to wear this style

It's all about long, over-the-knee-boots this season, isn't it? I think it takes some courage to wear this style, but they look strangely good with everything. I like them with quite normal, daytime looks, so they're a bit dressed-down. I'd avoid anything too Pretty Woman. They're such a fashion statement – it's a very strong look.

My boots were inspired by the Greenlandic kamik, a boot made of sealskin. They are part of their national costume and they're decorated with embroidery, leather appliqué work and seal fur; they're really elaborate and labour-intensive. My interpretation is more of a fashion take. They have a heel and are quite slim. They caused quite a stir in Greenland – there was even a protest march. If you want the Greenlandic look, then a pair of sealskin hotpants would be the traditional accompaniment – but this is not, admittedly, an easy look to pull off.

Manolo Blahnik, shoe designer: For me, boots epitomise sex...

Every year I have lots of boots in my collection. This year I have chosen something a little extreme – a paper-flat sole with lots of big buckles. I love this look – it makes me think of old films, of Margaret Lockwood, or crinolines. I love the look of a very long skirt with these paper-flat boots. Women in winter must wear very high or very flat boots, it's so chic – forget your pumps. Long skirts are a must in women's wardrobes, although you don't see many of them these days. It's what I would wear, though.

I love the touch of leather – it's so sexy; I have lined my boots before with cashmere and linen, even fine leather, which is so luxurious and sexy.

Every year I have done over-the-knee boots. One year they were so high you could tie them to your belt – Elle Macpherson in that was so sexy.

The sexiest ones were from a few years ago – they were black leather over the knee, cut in the front to show lace and Lycra, very, very tight, and they had these red heels which were so high. They were jaw-dropping, fantastic, like a huge sock but sexy. To me they epitomised sex, reminding me of Marlene Dietrich: I have a very cinematographic mind.

Pam Brady Accessory buyer at Browns: Length is key

I think that this season's key styles are super long, thigh-length, high-heeled boots such as those by Azzedine Alaïa, and Gianvito Rossi's long suede and leather versions have been flying out [of the shop]. The super-cool version by Balenciaga has had a great reaction.

The other key trend for us is "statement boots". Designers have been competing to come up with the most attention-seeking, coveted boots – whether they are laden with hardware, precious skins or the highest and most imaginative heel structures. Statement items include Alexander Wang's buckled, high-heel utility boots. Balmain's buckled-up tough ankle boots are definitely making an impact.

Alaïa never disappoints with studded ankle boots, and black-padded ankle boots toughen up any girl's outfit. The use of precious skins by Nicholas Kirkwood sees python and lizard booties making a strong impact. The price doesn't matter – statement boots are by far the best-selling items of the season. They are being described by the customer as works of art and rightfully so: true individuality can be achieved by a pair of boots.

Thigh boots are being styled with a number of different looks – as an accompaniment to leather mini-skirts, demure day-dresses, with chunky knits and loads of leather. You can change the look of the boot instantly or even add attitude to the most pretty shift dress for the evening. The use of luxurious suede, skins and hardware immediately adds fashion points and instantly makes any item of clothing look desirably expensive.

Anita Borzyskowska, VIce President, Gap: Ankle straps flatter

The response to the Pierre Hardy boots from the press has been phenomenal. Every fashion editor asks when they're going to be in-store, followed by a lightly apologetic "So I can get in the queue to buy myself a pair". Pierre Hardy is a shoe-design genius – he understands what women want to wear. I love the unexpected colours of navy, dark green and grey – still neutral enough to wear with anything. They look great with denim, and "lift" autumn's sombre colour palette. The platform makes the heel more comfortable to wear, and the strap at the ankle is very flattering. Also look out for the winter shearling version.

Nicholas Kirkwood, shoe designer: They are a symbol of independence

Ankle boots look best when worn with something that emphasises the shape of the leg, either skinny jeans or a short dress. Boots in general can transform a look: they are empowering and a symbol of independence. To me, they should strike a balance of the masculine and feminine.