I've been doing some research and already understood how the date would be converted to the roman calendar,but just the month and day (e.g. January 10 would be written as 'ante diem iv Ides Ianuarias) but how would I include the year in order to write, for instance, January 10,2010?
The current year is AUC MMDCCLXIX, that is, 2,769 ab urbe condita, "from the foundation of the city".
So you would say A D IV ID IAN ANNI AUC MMDCCLXIII.