By John Whiting Tax partner, PricewaterhouseCoopers LLP

DO...

• Read all the tax return questions carefully.
• Get all your paperwork together - such as your P60/P11D - before you start.
• Make sure any employment benefits that you list tie up to your P11D (benefits statement from your employer) and you make appropriate expense claims.
• Check the amounts you log for bank or building society interest received plus the tax that's been deducted (usually 20%) add up to the gross amount. (The same principle applies to dividends with the tax credit.)
• Include personal pension payments.
• List Gift Aid payments and any other charitable donations and enter the amounts you actually gave.
• Pay attention to the final questions on such things as married allowance (only available to someone born before 6 April 1935), bank account details (if you are due a repayment) and NI number (if not already included).
• Bear in mind that you can fill in your return online - and the HMRC system will calculate your tax bill for you.
• Compare it with the return you did last year as a 'sense check'.
• Use an estimate if you really can't get the precise figures in time - explain what you are doing in the 'white space' and send the correct figures as soon as possible.

DON'T...

• Miss out any questions that are set or the relevant additional pages.
• Worry about the pennies - you can round to the � to your advantage!
• Enter income from ISAs or PEPs.
• Assume all state benefits are tax free - the state pension is taxable, as is (for example) jobseeker's allowance; child benefit and tax credits are not.
• Ignore capital gains - they have to be included (on separate pages) but if your total gains are under �8,800 and total proceeds are under �35,200 you don't have to include details - see Q8 on the SA form.
• Leave it until the last minute - you are more likely to make mistakes if you rush it.
• Include normal pension contributions, or associated Additional Voluntary Contributions, made to your employer's pension fund.
• Forget to sign the form and keep a copy for your records.
• Forget that you actually need to pay any tax you owe by 31 January - it's not just a case of getting the form in. You may need to make your first payment on account for 2007/08 as well. (Interest at 7.5% runs on unpaid tax.)
• Think you can leave it to the last minute if you want to use the online system: you need to register first which can take a day or two to clear.

Finally, bear in mind that for the current year's tax return things change a little - the 31 January deadline remains, but only for payments and electronic returns.

Paper returns for tax year 2007/08 will have to be filed by 31 October 2008. The 30 September date (for HMRC to calculate your tax) disappears.