Think of it as the 'no flipping way'. You don't have to turn it (phew), but rotating your mattress regularly is one of the very few conditions of your warranty. Take it for a 180 degree spin on the base once a month for the first 3 months, then every 3-6 months for the rest of its life.
To make life easier for you, our mattresses come with handles for a simpler spin. (Due to it's light-weight, the Essential mattress in our Comfort range doesn't include handles)