When you start at Sunndalsøra you should drive against Øksendal (Molde), but instead of following the main road through the Øksendal tunnel you should turn right on old road outside the tunnel towards Viklandet. Run to where the road is blocked, there can be parked.
The walk up to Vettafjellet is one of the shorter top tours in Sunndalsfjella but still a very nice trip. The tour starts at 250 m on the road from Vettamyra. Here goes one clearly marked path up to Vettafjellet on 969moh. The trail has good climb all the way.
From the top of Vettafjellet have good views both to Øksendal and Sunndalsøra and the surrounding fjords. If you get there at the right time, you'll have a panoramic view of the sunset!