You need to register the lyrics with a bureau. This costs money. The amount depends on how you want it copyrighted (there are many formulas). I don't know all the different bureau's in England, I know them for Belgium, but you aren't helped with that I suppose...
Contact the organization that you must pay money to play music on parties and so. They are also handling this kind of thing and/or can give you more info and/or redirect you. (For Belgium, this is
Sabam, and they will send you to a bureau like
Almo, etc...)
On the internet you can find also some info:
http://www.justplainfolks.org/ubb/Forum11/HTML/000397.html
http://www.patent.gov.uk/ (click on copyright)
http://www.intellectual-property.gov.uk/
note: You will read and hear about the poor-mans-copyright-method... This means: sending your material to yourself in a closed envelop (and don't open it up), so that the date is registered. Although this is a form of copyrighting your material, this will not hold up in ANY court and has NO legal benefits... The point in copyrighting your material in a good way is that other people A) can't steal it and B) you can make money with it, because other people need to pay to use it....
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