If your child is finding it to hard to relax, ensure you are relaxed and grounded and they will begin to match your energy. Imagine you are a bee, buzzing along thorough the air, take a deep breath in and feel your body vibrate as you buzz, then exhale letting your breathe out making the buzzing sound for as long as possible. Fly like a bee in your imagination into a meadow and find a place to rest your buzzing body. Pause and look around for flowers- describe the setting where you have landed...continue the story focusing on breathing and relaxing and allowing the bee to on a journey. There are lots of relaxation stories online so google them and pick your favourite.