You can go over Mt Hood or take the Santiam pass from Salem. From Portland, it’s a little quicker to go the Mt. Hood route and the pass is usually easier in the winter. Regardless of which pass you take, you want to end up on 97 south.
The Mt. Hood way:
Take I-84 to the Wood Village exit. Stay on 26 East for ~100 miles, following signs to Mt. Hood. (After Government Camp, you’ll come to a fork in the road. Just keep following signs to Bend/Redmond. Do NOT go towards Hood River and Meadows.)
Merge onto 97 South towards Bend and drive ~56 miles. (there will be signs) Stay on the highway – you don’t want to take the business loops for Redmond or Bend.
Take the Century Drive exit (#153) into Sunriver. At the traffic circle, take the first right onto Abbot Drive. Turn right onto Abbot House Lane, just past the grocery store. The condo is #10, last one on the lower level.