Obtain an Oregon state driver's license. Owning an Oregon state driver's license is evidence that you intend to reside in the state on more than a temporary basis.
Register to vote within the state of Oregon. Voter registration is evidence of your intent to reside in Oregon, sufficient evidence to establish Oregon residency. You can register to vote at the Oregon Secretary of State website.
Live in Oregon for a consecutive period of 12 months prior enrolling in school. Two exceptions exist to this time period. First, if you depend on your parents for financial support, and they moved to Oregon for a reason other than your school enrollment, you become a resident immediately upon moving to the state. Finally, the time period is reduced to 6 months if you are an independent student who moved to Oregon for any reason other than school enrollment, such as an employment opportunity.