The model-turned-actress-turned-singer is so last decade. The modern celeb can do everything. For proof of this, look no further than the phenomenon that is MaryKateandAshley Olsen. This tiny duo - barely into their twenties - head the billion dollar Dualstar empire, whilst at the same time managing university studies, eating disorders and tough fashion choices.

Eat your heart out Paris. The hotel heiress isn’t far behind however, with Paris paraphernalia raking in a reputed £100-million a year. Allegedly charging $200 000 for a 20 minute appearance at parties, the blonde socialite has proved that – despite a complete lack of talent – she is a force to be reckoned with.

Her contributions to the 21st century include an autobiography, a perfume line, a clothing/jewellery/handbag line, a pop album aptly titled ‘Paris’, a sex tape, a television series and, briefly, a nightclub called Club Paris. Having fully grasped her value as a commodity, Paris even attempted to trademark her favourite exclamation, ‘That’s hot!’

So, how do you – the Oscar-winning actor or almost-famous celebrity wannabe – go about establishing your business empire? We’ve put together a sure-fire five-step formula guaranteed to bring you more fame, more cash and more credibility. Okay so maybe not the last one…

Step one: your own scent

Because everyone wants to smell like their favourite star (duh!) this is the perfect way to get your image…um I mean scent…out there and bring in a wad of extra cash. The effort/profit ratio is also very good, with minimum effort (photo shoot and random perfume selection) resulting in maximum profits.

J.Lo, Britney Spears and Paris all have a range of perfumes sporting their image. For the slightly older demographic, there are perfumes ‘by’ Isabella Rossellini, Sarah Jessica Parker and Celine Dion, while tweens/teens can spray on the spirit of Hillary Duff and Lindsay Lohan. For the sporty there are scents by Maria Sharapova, Andre Agassi and David Beckham.

According to Forbes, P. Diddy’s perfume Sean John Unforgivable raked in an incredible $74.9-million in 2006. Proof that your perfume can out-perform your disastrous personal life can be found in the fact that two of Britney Spear’s perfumes brought in $84-million last year, while Elizabeth Taylor’s White Diamonds is still fetching $60.7-million a year.

Step two: your own clothing line

Once you’ve conquered the olfactory realm, it is time to move into the fashion world. Anyone can dabble in a few T-shirts and handbags (Olsen twins, Hillary Duff, Mandy Moore, Jessica Simpson and Nicky Hilton), but if you want a truly successful clothing line, you first need to develop a distinctive fashion style.

Gwen Stefani’s slightly whacky, but undoubtedly cool, fashion choices make her label L.A.M.B so successful, while Sarah Jessica Parker – a fashion icon from her ‘Sex and the City’ days – has created a reputable label in her Bitten. Although her partiality for fur has earned Jennifer Lopez the hatred of animal activists, her clothing lines JLO and Sweetface are considered decent enough to crack major fashion shows. Beyonce has enlisted the help of her mother Tina Knowles in the creation of her grandly-named line – House of Dereon.

Male celebs are increasingly finding their way into fashion business with notable hip hop artists at the forefront. P.Diddy’s line, which was launched in 1998 and features lots of bling and suave suits, has generated millions of dollars in profit. Earlier this year, Jay Z sold Rocawear – the urban-style apparel line he co-founded with Damon Dash – for $204-million.

Step three: write a book

Contrary to popular belief, books are not an antiquated endeavour. Proof: J.K. Rowling. You don’t actually have to write the book – because, let’s face it, not all celebs are gifted with fine prose, articulation and insight – that’s what ghost-writers are for.

Almost all the up-and-coming celebrities have written their autobiographies by the ripe old age of 21. Paris revealed the ‘secrets’ of her very public life in her autobiography ‘Your Heiress Diary: Confess It All to Me’, while Britney Spears has felt the need to publish two autobiographies (co-written with her mother Lynne) tracking her meteoritic rise to fame – ‘Heart to Heart’ and ‘Stages’.

Hardcore angry rappers and hip hop stars are not exempt from the book writing club. Eminem penned the suitably angst-filled ‘Angry Blonde’ and hip hop star 50 Cent tells the story of his life in ‘From Pieces to Weight: Once Upon a Time in Southside Queens’.

More risqué reading matter can be found in Jenna Jameson’s autobiography ‘How to Make Love Like a Porn Star’. Madonna shocked the more conservative echelons of society with the publication of her sexual fantasies in ‘Sex’ (followed more recently by a number of sweetly didactic children’s books), while the exhibitionist Lindsay Lohan plans to publish a collection of sexy snaps of herself tellingly titled ‘Narcissist’.

Others, such as Pamela Anderson (‘Star Struck’) and Nicole Richie (‘The Truth About Diamonds’) have tried to establish themselves as legitimate authors by publishing novels. At the other end of the spectrum, Angelina Jolie has jotted down an account of her travels and her encounters with various refugees – ‘Notes from My Travels’.

With so many celebrity books infiltrating the literary world, there really is very little reason for the public to read real books.

Step four: get into the hospitality business

When it comes to business ventures, networking is important. If, as a celebrity, you happen to be friends with some other celebrities, open a restaurant and invite them for dinner. Everything else will follow naturally.

Robert De Niro, who co-owns the trendy Nobu, Ago and Layla restaurants, seems to have cottoned on to this technique. Britney Spears’ Manhattan restaurant Nyla was forced to close after a mere seven months due to bankruptcy. However her ex-flame Justin Timberlake seems to be profiting considerably from the hospitality business as the co-owner of the restaurants Destino, Chi and Southern Hospitality.

Other celebrity restaurateurs include Jennifer Lopez, who owns the Cuban/PuertoRican themed Madre’s, Kevin Costner, who owns The Clubhouse and Julian Lennon, who is a part owner of the sushi restaurant Blowfish.

Step five: flaunt your eco credentials

If you’ve got it, flaunt it. Not everyone can crack the notch (yes, J.Lo, we’re looking at you), but being eco-friendly is so hot right now. Brangelina drives hybrid cars, Leo made an eco documentary and Steve-O is in a no-fur advertisement.

So, how do you turn all this goodwill into a money-making venture? Val Kilmer is planning to build a high-price eco-village on his 6000 acre ranch, while Leo DiCaprio is teaming up with the owners of Four Seasons Resorts to build a ‘green hotel’ on his Belize island.

Hemp enthusiast and vegan Woody Harrelson once owned an O2 bar and restaurant in West Hollywood, where patrons could breathe in specially oxygenated air. His latest venture is an organic food delivery service – Yoganics – which he owns with his wife. U2 front man Bono has a clothing line called Edun (nude spelt backwards), which specialises in clothing made completely from organic materials.

Please note: You can combine step five with steps one through four. Although there is no definitive proof, the following usually lead to an increase in income and have very little negative effect on your saleability: a stint in prison, a sex tape, an affair, strange sexual fetishes and a complete lack of talent/intelligence/personality.