Crucifix requires you to lay on your back and place feet flat on the floor with knees and ankles together. Take the arms out to the sides at shoulder height and put palms flat on the floor, this helps give you a bit of stick. Roll the knees to the left hand side keeping the knees and ankles together go as far as you can aiming for them to touch the floor. Both shoulders should remain in contact with the floor and let the head roll to the right hand side taking the twist all the way through the neck. Use your breath in to bring you back to centre.