At Trinidad and Tobago's carnival, fashions are as loud as the steel bands and the party continues until dawn. Noo Saro-Wiwa joins revellers at the forefather of Notting Hill's carnival

For non-dressy types, the fashion exuberance in Trinidad can leave you feeling shamefully dowdy. My simple T-shirt, jeans and lace-up shoes combo looked rather ascetic compared with the bikini tops, fluorescent vests and cleavages sauntering around me in Port of Spain, Trinidad's capital city. Carnival had barely begun, yet even the Trinidadians who weren't in costume made me feel like a nun in sackcloth.

Trinis love to dress up, and their carnival, the evolutionary ancestor of the Notting Hill version, is the perfect excuse for them to tart up like no other nation on earth. Carnival has been celebrated here since the 19th century, when emancipated African slaves and Indian indentured labourers began copying the fancy dress parties of their French colonial landowners, and mixed in elements of their own African mythology and traditions.

The saying goes that if Trinibagonians aren't celebrating carnival, they're getting ready for it while reminiscing about the last year's festival. Although Tobago holds its own small festival, people from all over Trinidad and Tobago, and the Caribbean, converge on Port of Spain for the biggest and best-known carnival in the Caribbean. It's smaller than Rio de Janeiro and Notting Hill, with around 300,000 people marching through a relatively compact area of the city around Queens Park and the national stadium.

Arriving in town on a Saturday evening, we took a walk around Queens Park, where the streets were jammed with people and food and rum stalls. Though we were among 40,000 foreign visitors (half of whom are American), our presence didn't dilute the Trinidadian flavour much. Dotted around the park were various steel bands competing to win the Panorama steel band title, with about 20 musicians on steel pans, guitars and a full drum kit playing calypso tunes, as well as Latin and jazz standards. The steel drums evolved from the oil drums and frying pans that were used to create African percussion almost a century ago, and the fullness and intensity of the rhythms sounded more like Brazilian bloco street bands rather than the modest trills of steel pans in London.

Next day was Dimanche Gras (Big Sunday). We attended the costume competition in which people compete to win the titles of King and Queen of Carnival. Participants have been trying to outdo one another for so long, it's hard to see how much further they can take it: outfits included 20ft chandeliers, ruby brooches, and giant duelling ants. The constructions are so large they're supported by metal scaffolding and pulled along on wheels. One ambitious competitor chose to walk on stilts – a decision she may have regretted when she collapsed, split-legged, on to the floor to howls of sympathy from the audience. It took four men to dive beneath her tent-sized skirt and help her up again. In the end, the winner was "Pacific Tsunami", a colossus of billowing blue fabric.

By 1am, my friend and I collapsed into bed in a jet-lagged heap, but for Trinis it was the start of the main phase of the celebrations, J'ouvert. Derived from the French "jour ouvert" or daybreak, this street party signifies the real start of carnival. At around 2am, revellers smear themselves with colourful paint, mud, powder or oil. By the time I woke up the next morning, white-powdered zombies and green hulks were still dancing through the streets.

The main event had now begun. Costumed revellers organise themselves into groups, known as "playing mas" and parade through the city. Mas camps vary in size. One of the biggest and best-established, Tribe, includes a mix of Trinis and tourists (often American college girls and frat boys) wearing Amazonian facepaint, feathers and not much else. They and other mas camps with names like The Riddimholicks and Wild Ting cavort through the streets, dancing to modern soca, which has fused with Jamaican ragga to form ragga soca, a fast beat that pounds out of speakers on trucks rolling slowly through the crowd.The mas themes are eclectic: a group called Ye Olde England minced delicately in Tudor garb; geriatric mas players in sequined suits shuffled their feet to a gentler, old-school soca tune; Roman gladiators in sunglasses and shiny biceps dry-humped their female counterparts.

The tradition of "wining" (gyrating of the hips) is a mutation of an African tradition. Edward Long, an 18th-century historian, once said of the Carnival woman: "In her paces she exhibits a wonderful address, particularly the motion of her hips and steady position of the upper part of her person." But by 1877 the Trinidad Guardian newspaper was calling for "a refinement of our vulgar tastes". The authorities tried to ban such revelry, but failed. These days, wining is even racier. Women rub their bottoms against the men (or vice-versa), and some people even get horizontal for a few seconds of full simulation. But for all its raunchiness, it is just innocent fun, and when a lady rubbed her bum against my friend's trouser zipper, he played his part without getting in a fluster.

By late afternoon, only detritus and the echoes of distant soca beats filled the streets. Our heads were spinning from knocking back Puncheon rum and staying awake for the best part of three days. Carnival was over and Trinidad returned to its soporific pace, as if conserving its energies for these few insane days before the start of Lent each year.

Next morning, we took a taxi out of town, through the forested hills to the beaches of Maracas Bay on the northern coast. I gorged on "bake and shark" – deep-fried shark stuffed in a deep-fried batter roll – and stared into the Caribbean sea wondering when – not if – I'd come back to Trinidad for more Carnival.

• Buy Noo Saro-Wiwa's memoir Looking for Transwonderland: Travels in Nigeria from the Guardian bookshop site (£11.99).

Getting there

British Airways flies from Gatwick to Port of Spain from £719rtn

Where to stay: Coblentz Inn Boutique Hotel, 44 Coblentz Avenue, Cascade, Port of Spain; +1 868 621 0541

Carnival dates: 20-21 February 2012; 11-12 Feb 2013