How i do accounting of an event?

Dear Sir/Madam My friends are organise an event about animation at a large scale,which includes sponsorship from various entities and also having big expenditure for inviting guess from that field.I want to know it is just an event,not an entity so how I do accounting of it it start from March2013 and end on 15/0 4/2013.Am I do accounting for two periods from 01/03/2013 to 31/03/2013 and from 01/04/2013 to 30/04/2013.please help me and if any suggestions you have please kindly send me. Thanking you