There are plenty of aspects of body language that you can worry about during an interview, but the basics matter more than all the minor details. Case in point: eye contact.
Interview picture from Shutterstock
A survey of 2201 managers by CareerBuilder found that 70 per cent had noticed interviewees failing to make eye contact. That figure suggests both that it's a prevalent mistake, and also it's one that managers are highly attuned to.
The survey also unearthed other common errors (not smiling, bad posture, fidgeting), but the dominance of eye contact suggests that this is something to concentrate on. An interview is not the time to be shy. Look your interviewer in the face. Shyness is a habit that can be broken.