There are some common pitfalls that can make our pose to look unnatural. The position of the head is one of those. If we take a look at photos of people involved in activities such as surfing, we can see that we humans try to level our head as much as possible. The head just doesn't stick out from the shoulders in a perpendicular fashion. To illustrate this point, let me show you an image of the model with the chest positioned almost at the right angle, but with the head unchanged from the default position.

There is an unnatural stiffness to that head. Just a little bit of rotation and side-to-side bend makes the pose look much more natural. Here is the difference:

This looks much more natural even with the "dead gaze" typical of the default configuration.

The Head and Neck parameters are often very useful, and it can be easier just to work directly with those instead of trying to move the body part directly. Here is a screenshot of the parameters used to position the head in the preceding image:

Bend moves the chin up and down, Twist rotates the head along the vertical axis, and Side-Side moves the head toward one shoulder or the other.

The neck has similar adjustments. Keep in mind that it's important to distribute the movement of the head between the neck and the head body parts in order to make the movement look natural.