Celebrities across the globe are rocking the humble onesie and if Brad Pitt and the One Direction boys can wear a onesie and look sexy as hell, so can you. Just follow these tried and tested onesie-wearing rules.

1. Wear your onesie with confidence

Friends and family may mercilessly mock you for choosing to wear a onesie, but as long as you think you're cooler than a cucumber, that's all that matters. You need oodles of couldn't-care-less-about-what-anyone-else-thinks attitude. After all, it doesn't matter if people are talking about you behind your back, it just means you've scored yourself a fan club.

2. Make sure your onesie has "stop and stare" factor
Forget boring old cheetah, leopard or tiger prints. Choose something that's side-splittingly hilarious and sums up your personality — like a sexy little devil, a T-Rex, a superhero or a cartoon character. People are going to laugh anyway, so why not give them their giggle for the day.

3. Choose a onesie with a window
The problem with non-window onesies is when it comes to going to the bathroom. Stripping off isn't too bad during summer, but those bitterly-cold winters can be problematic. Also, getting your gear off in a public toilet can be a bit gross. Not all onesies come with exit hatches, so perhaps if you are handy with a sewing machine, you can insert your own.

4. Size is everything
Onesies are not the most flattering fashion item. Opt for a larger size than you normally would. If it is one size too small, you will find that it clings to all your lumps and bumps, leaving nothing to the imagination. Bigger is always better and, if you can, try before you buy as sizes may differ.

5. Shake off your tail feathers
Koala Onesie
Image: Onesies
You'll be laughing when you purchase an animal or cartoon character onesie with a tail. Just be warned: Onesies are all about comfort. Tails may be hilariously funny, but they're not comfortable to sit on. They also tend to dangle down the toilet bowl in the middle of the night when you're half asleep.

6. Strength in numbers

Too shy to wear your onesie in public? Gather a group of your closeted onesie-wearing friends and go out as a group. You'll feel more comfortable if you have friends who look sillier than you do.

7. Build up to a public outing
Start out with small onesie-wearing expeditions, like a quick dash up to the letterbox or leaning over the fence talking to the neighbours, until you're confident enough to do a midnight dash to a 24-hour supermarket or drive to pick up the kids from school.

8. Glam it up
Miley Cyrus in onesie
Image: Miley Cyrus/Twitter
Accessorise it, baby! Wear sunnies, complement it with a snazzy handbag and team it with your favourite pair of shoes. Being comfortable doesn't have to mean looking drab.shoes. Being comfortable doesn't have to mean looking drab.

9. Walk with swagger
If you're going to wear a onesie, you might as well wear it well and you can't do that without a bit of swagger. Walk around like you've got the moves like Jagger.