I'm here to validate that it is, in fact, more difficult than it sounds. Our first job is safety; our second is competitive steering. Every touch of the rudder will throw off the set and increase drag, so the less we use it, the more speed we add to the boat. We may have heard to only steer on the drive; doing this protects the set and forces us to make smaller adjustments. Steering on the recovery will be more responsive, but generally slows the boat considerably.
Many teammates and coaches offer us helpful advice on points, but in an 8+, we often can't see over the head of our stroke. What can help? Each of us will click with something different, but here are a few tricks I use to hold onto a point.
I hold the steering extremely tightly. In a 4+, I hold the lever with two fingers and tense my forearm. In an 8+, I grip around the gunwale and only use my thumbs to push the knobs. This stops me from making broad motions with my hands because each movement feels like exertion. For others, a loose grip better allows for small controlled movements, but a tight grip has helped me.
If I can't see it, I'm pointed at it. In an 8+ I choose my point and then try not to see it. If it's hidden directly behind my stroke, I'm holding the point.
Choose a point off of my stroke's shoulder. If the same point in the distance stays in the same place off of my stroke's side, I know I'm holding a straight course.