If your turn over is less than £150,000 per year, I recommend that like me, you sign up for the Flat Rate Scheme. It means that although you still have to keep your books, it takes about 2 minutes every 3 months to work out your VAT. You just add up the VAT inclusive value of the invoices you have issued and take a percentage (depending on what sector your business is in...mine is 10%) of that value and thats what you owe HMRC. So say you issued £12,000 of invoices in a quarter and your rate was 10%, you owe £1,200 for that quarter...its easy peesy! I worked out that using the scheme, I saved about £3,000 VAT per year. More details at
http://www.hmrc.gov.uk/vat/start/schemes/flat-rate.htm