If your grouchy teen is making family life miserable, one of the authors of a new book gives tips on how they can be their brilliant best self – making everyone in the family much happier again

Everyone is familiar with the cliche of the typical teenager who stays in their bedroom, communicates in grunts and monosyllables, and appears to hate just about everyone.

They don’t appear to be happy, and their parents, family and teachers are definitely not happy.

But things doesn’t have to be like that, and a new book, aimed at teens themselves rather than their parents, is here to explain why, and to, basically, tell them how to cheer up.

The Art of Being a Brilliant Teenager is no weighty self-help tome with long chapters of turtuous grown-up advice about being a decent young person. Instead, it’s packed with cartoons and scrawled writing, under chapter headings including Bouncebackability, Phone a Friend, You are You, and Being Real.

The book, written by three experts on happiness, psychology and being brilliant, claims to be “for ambitious teens who are ready to become proactive, determined, successful and most importantly: happy! And for parents and teachers desperate to turn a down-beat teenager into a ray of positivity and delight.”

So how do you turn a teenager into this ray of positivity and delight?

It sounds like an impossible transformation for most adolescents, and the truth is, says the book, that for it to be “Saturday morning every day in your head” teens need to be awesome, which apparently takes “a tad more effort”.

That extra effort involves standing out from the crowd by ‘doing stuff’ – even though it’s easier to do very little, choosing friends carefully, and making the most of your family because it’s the only one you’ve got.

In a nutshell, the idea is for teens to strive to be the best they can, rather than taking the easy way out and fitting in with everyone else.

One of the authors, teacher Andy Cope, highlights a quote by the happiness expert Gretchen Rubin, who said : “Any family is only as happy as the least happy child.”

“That’s so true,” Cope says. “It only takes one miserable teenager to ruin the whole balance of the household.”

So to get the balance right, teenagers need to raise their game – now.

The book points out that people often say someone simply hasn't found themselves yet, but it then stresses: “The ‘self’ isn’t something you find, it’s something you create. Create your best self and be it consistently.”

One of the many ways of doing this is by simply smiling, rather than spending a fortune on clothes, and makeup and walking round scowling. People are much more likely to remember a smiley teenager than the one with the most expensive trainers.

“You can order them to smile till you're blue in the face,” says Cope, “but if parents smile first it’s the best way of getting teenagers to do it.”

And as well as smiling, teenagers would do well to adopt the ‘four minute rule’, as the authors say the first four minutes of any interaction are the most important. So, being the best, positive and enthusiastic version of themselves for the first four minutes after meeting someone will have a significant positive impact.

Then there’s also negative thoughts and behaviours. The authors point out that ingrained, negative thoughts like ‘I’m rubbish at that’, or ‘I’m not confident enough or pretty enough’ etc, and negative behaviours like watching too much TV, or eating too much junk food, stop teenagers being brilliant.

The way to get rid of negative thoughts and behaviours is firstly to identify them, and realise they're holding you back, says the book.

Then instead of dwelling on such negativity, teens should list 10 things they already have and really appreciate, but take for granted.