Tax return submission - CLEARBOOKS

From November 2011 to March 2012 I was self employed as a web designer / online web video provider. I was correctly registered and have kept online records using Clearbooks. I have some equipment that was used for business - some purchase prior to set up and existing for which receipts exist. I just need to complete and online submission and state CLEARLY that the business was closed as of my last invoice back in March. In that short time around £3000 was taken so should not be too hard but need to get it right. Can you help??