Nearly half of young people think school careers advice is confusing and unhelpful, a poll suggests.
Young people are not playing to their strengths
One in 10 claim to have had no careers advice during their education.
Around two thirds have not decided on a career by the time they leave school, says the YouGov poll for recruitment consultancy Harvey Nash.
Most rely on friends but many are turning to the internet for advice instead and the careers service needs to embrace this, say experts.
The knock-on effect of confusing and unhelpful careers advice is that young people are not making the best use of their skills and industry is losing out on the most talented candidates.
Harvey Nash chief Albert Ellis said: "Without direction and advice, not only are young people missing out on potential career opportunities themselves, but businesses too could be missing out on the next generation of skills they need to compete."
Newspaper columnist and former Conservative MP Matthew Parris's experience left him bemused.
He told BBC Radio 4's Today programme it had amounted to being "advised to be a spy" while at university.
He said: "He actually sent me down to MI6 and I went for all sorts of tests and interviews and was offered a job in the end."
He realised espionage was not for him and turned it down in favour of a post at the Foreign and Commonwealth Office, before going into politics.
He said: "I do think that if people want advice on how to find out about engineering or law, who they should go and see, where they might get a bit of summer experience, that's fine, but the idea that anyone should guide someone at the age of 18 or 20 into what they want to do if they don't know what they want to do is all rather implausible."
The YouGov survey of 1,054 working adults between the ages of 18 and 30 discovered that only 35% felt formal careers advice helped them make decisions about their career, while 62% had not decided on a career before they left school.
It found that individuals would look to friends and colleagues for advice first (72%) and online job sites second (52%).
In addition, 40% of respondents were regularly logging onto Facebook and MySpace.
Some young people (5%) were already using these sites for careers advice and professional networking and the YouGov research shows this figure is likely to rise in the next few years.
A quarter of those taking part in the poll said they would use a networking site as a channel to receive careers advice and a futher third would consult online forums or blogs.
Matthew Parris was advised to become a spy
There is still a place for careers advice in schools but it has to be more tailored to the individual, according to Professor Mike Campbell, director of development at the Sector Skills Development Agency, which is trying to address the UK's growing skills shortage.
He said: "Web 2.0 and the advent of social networking have changed the way in which young people embark on and develop their careers.
"Young jobseekers are becoming increasingly disengaged from traditional careers services and practices.
"They want a personalised approach, customised to their own 'profiles', and as a result more and more are resorting to their own initiative to develop their careers and contacts online."