You'll need to fill out a Certification of Oregon Residency or Domicile (Form 735-7182) and provide documents to prove Oregon residency. Any Oregon state tax return document will satisfy requirements. If you do not have tax return documents, you can provide any 2 documents (or more) form the following list:
Property tax record.
Rental or lease agreement.
Any type of receipts or documents showing that you have been in Oregon for 6 months of the year.
Current bank/credit union account that has been active for at least 60 days.
Receipts of Oregon public assistance.
Oregon voter registration card.