First of all if you want to drive in Italy on a license not issued by a Eu member state, it is recommended to contact the Italian Embassy in your country before moving.

Driving in Italy with a valid Non Eu licence and up to one year after moving your residence in Italy, is allowed ONLY IF the licence is:

• accompanied by an International Driving Permit (IDP), issued by the foreign country that released the driving licence
  OR
• accompanied by a certified translation

The driving licence should be translated by:

• the diplomatic representative of the country having issued the driving licence and then legalized by the local competent Prefettura offices
  OR
• a translator (anyone who has the language skills to translate the document) and then certified (asseverata) at the local Courthouse.

If you move your residence to Italy, you have 1 year time to exchange (conversione) your driving licence provided that:

• there is a mutual recognition agreement between Italy and the country that had issued the driving licence
• the licence is still valid;

If it is not possible to exchange it, you need to get an Italian driving licence. Theory and practical tests are required.