I was taught to "drag in" for a cheek weld. Place the chin on top of the stock and let your head drag down, pulling the cheek up, until your eye is in the line of sight. Don't force yourself fore or aft - move the scope to match your head position.
If firing multiple shots from one position, don't break the cheek weld when cycling the bolt. The inline stock design allows this.
The rifle shouldn't be low enough that you're looking through your eyebrow and straining your neck, and not high enough to strain your back.
For sling shooting, lifting the right leg can take some pressure off the lungs, bring the rifle closer inline with the body, and tighter into the shoulder. During the rapid fire string of Across-The-Course, the straight leg position is more likely to loosen at the upper body, resulting in a strung out group.