Reporting Rent a Room Income for 2008

Hi all, just a quick question that I hope is simple enough to answer.
Mainly down to ignorance of how the scheme works, I didn't declare my income from rent a room scheme for 2008. I'm looking to submit it now but I'm not sure how I would go about it. I have form 12 for 2009 but how would I submit 2008 now?

Any guidance would be appricated!

Thanks

If you have already submitted a Form 12 for 2008 then a letter stating the omission will suffice.

Otherwise just submit a Form 12 for 2008.

Thanks. Didn't know if there was something extra I had to do. Didn't submitt a form so I'll just submitt one.

Thanks

Sorry one more thing, I have form 12 for 2008. Should I only fill in the section for rent a room or do I have to populate everything? I.e. DIRT etc
thanks

The form should include all sources of income for 2008, including employment income, deposit income etc etc