Keeping the core engaged, as Brookes stated, will assist in taking pressure off the head and neck (think no WWF wrestling move here

. Actively press the tops of your feet and the shins into the mat to assist with anchoring the body and balancing the weight distribution. Keep the chin tucked into the throat and that will help w/ getting the top of head flat to floor not the forehead/face to floor (which I think I did for a good year before I finally got it right

It's such a great posture and once you get it down you will love it
Go to a Wood90 class and stay for the posture lab and ask the teacher to help guide you through the pose. Wood90's are an awesome chance to get some additional assistance

Metal workshops are coming up and rabbit pose is in that series! Look into attending, they are a ton of fun!
Peace and Yoga,
Allie