More than half of us dream of making a fresh start in a more rewarding career, switching the office for a classroom or setting up a small business. However, careers advisers say that such decisions should not be taken lightly.

Pam Kingsland, who left a job as an investment banker in the City ten years ago to become an occupational psychologist at Career Analysts, the consultancy, says: “Unhappiness in your current company, bad relationships with colleagues or pressure from your spouse or family may not be the right reasons to leave your present career behind.”

“Of course, many of the thousands of workers who are facing redundancy as the recession bites have no choice and are forced to change vocation.”

No matter what your circumstances, the prospect of embarking on a new career can be daunting. However, careful planning and the right help makes it more likely that you will succeed in your endeavours. Here is our five-step guide to the costs and rewards of changing career.

Identify your dream job

Not everyone who wants to find a new career knows what job they want to do. Cath Roan, of Careershifters.org, the specialist website, says: “You need to take a step back and get to know yourself again. Sometimes you forget what your interests are and what you are passionate about. People can lose themselves in a job so you need to find yourself again.”

If you require help to define your future direction, you could pay a professional careers adviser. Occupation psychologists break down the process into four areas: your interests, personality, aptitudes and values.

Ms Kingsland says: “The process can help to identify what opportunities are available. It is very much based on each individual.”

Harry Freedman, chief executive of Career Energy, another consultancy, says that there are certain jobs that attract more interest than others. “We have a lot of clients seeking to move into environmental positions and areas such as corporate social responsibility. Teaching also remains a very popular vocation. Some people want to transform their lives, others simply want to tweak the path that they are already on.”

Career Energy offers professional careers advice and guidance, charging between £499 and £2,550 for the full career-change programme. The cost of a programme for executive-level clients is higher.

Career Analysts, based in the City of London, charges between £495 and £695, depending on your age and experience, for a day of psychometric testing, aptitude tests and guidance.

The government-funded Careers Advice website has detailed information on different jobs, as well as advice on career training and the job application process. You can also call an adviser on 0800 100900. Prospects.ac.uk, the graduate careers website, is another useful tool for researching opportunities, while The Age and Employment Network offers free careers advice to those in middle or later life. You can call the service on 020-7843 1590 or visit www.taen.org.uk.

Do the research

Once you have settled on your chosen career, the next stage is to research the role thoroughly to find out what training or experience you may need to land a job. Speak to people who are already working in your dream role and make contacts in the organisations that you want to work in.

Suzy Greaves, a career-change coach at the Big Leap Coaching Company, says: “It also helps to read inspiring case histories of other people who have changed careers to show that the route is not always direct. You need to think creatively.”

Planning and support

Changing careers will not happen overnight. Experts say that it can take as long as three years, from the moment that you decide you want a new start to the day that you begin work in your dream position.

Ms Kingsland says: “You will need to look at your finances and identify whether you can afford to reduce your current hours to make time for training, or will be able to afford a pay cut with your current commitments. Budgeting is key.”

You may need to build a nest egg to cover periods when you are out of work while looking for a new job, or to cover the cost of retraining. Draw up a comprehensive monthly budget, detailing all your ingoings and outgoings. Money management websites such as Kublax.co.uk could help.

There are also a number of career-change forums that can help you to talk about your plans and gain ideas and advice from other people who are already working in your chosen field. “Your friends and family can get tired of listening to your hopes and fears,” Ms Roan says.

Job websites, such as Monster.co.uk, also have discussion forums. Alternatively, visit the informal mentoring website Horsesmouth.co.uk. If you work or want to move into the media or creative sectors, you could also visit ScannerCentral.co.uk.

Careershifters.org recently started the Shift Club, an online forum that allows members to speak to other career changers and obtain guidance from professional advisers online. It costs £67 to join for three months.

The right training

While certain careers require extensive training, there are others that value experience more highly.

Training to be a teacher, an architect or a lawyer will be costly and take time. However, other professions may require only a short course to obtain the necessary qualification and periods of work experience or volunteering. It can take time, and a patchwork approach, using all routes, may be the best way to improve your CV.

You may find that you already have the skills needed to break into your new job. Ms Greaves says: “A lot of people have fantastic transferable skills. If you do need retraining, it does not necessarily mean going back to university.”

Use job and careers websites and speak to the human resources departments of companies working in your chosen field to find out what you need before applying.

Finding the perfect position

Once you have completed the appropriate training, it is time to re-enter the jobs market. Update your CV, practice your interview technique and use the contacts that you have cultivated to take advantage of any openings.

Ms Kingsland says: “You have to be realistic and persistent. Once people work out what they want to do, they tend to shoot off like a rocket. But it can take time and hard work.”

Case study

Dan Williamson quit his job as an IT project manager to become a humanitarian aid worker for Médecins Sans Frontières. In September he is enrolling on a master’s course in violence, conflict and development, part-funded by the French aid charity.

The 33-year-old Londoner had been in his previous job for five years when he decided to change career. “It was an interesting job, but I knew that I wanted to try something new, I just didn’t know what,” he says. “I would wake up in the morning and want to be an architect, but the next morning it would be a teacher.”

Mr Williamson contacted Career Energy, the career consultancy.

“I got a lot of help pinpointing the right kind of job for me. It turned out to be as a humanitarian worker. There was definitely an enlightenment moment, which was really exciting.”

He spoke to people in the field, making contacts and finding out more about the role. He also went on two training courses and found a job after three months.

The jump from IT to humanitarian aid has not only changed Mr Williamson’s working life. He has also given up his house, car and taken a substantial pay cut.

Last week he returned from a nine-month project in Darfur, Sudan, and before that he was working in Zimbabwe. “I changed my life completely and I don’t regret it,” he adds.

Setting up your own business

Thousands of workers decide to set up their own businesses each year. The steps that you need to take will depend on the kind of business, but here are some points to consider.

A business plan that lays out a clear strategy and objectives is essential, particularly when seeking funding from lenders.

You need to decide on the legal structure of your business — a limited company, self-employed sole trader or partnership.

Pick a suitable name for the business. If you choose to be a limited company, you will need to register the company name with Company’s House.

If you need premises, look for a cost-effective location that will balance convenience for customers and suppliers with the rent that you can afford to pay.

There are various taxes to pay and accounts that you need to keep. Seek the help of a tax professional and make sure that you meet all tax deadlines.

Initial set-up costs are considerable. If you cannot use savings or loans from family or friends, you could approach a bank. You may qualify for help from schemes run by the Government or charities. For more information, go to www.businesslink.gov.uk . or careersadvice.direct.gov.uk.