'ello,
well it depends what type of psychologist you want to be? Initially the best thing to do is to enrol on an accredited psychology degree, it has to be accreddited by the BPS in order to gain GBR and GM which allows you to become a member of the society. Then usually you can specialise in the particular area you want to go in by doing a masters or a Phd. There are a lots of different kinds of psychologist; occupational, cognitive, sports, clinical, educational ... list goes on ... basically u have to become chartered in order to work as an official psychologist ... try this link its the British Psychological Society .... it tells you what courses are accreddited, what careers there are and lots of other useful things!
http://www.bps.org.uk/index.cfm
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