King, queen or single? If you’re sleeping with your partner, don’t choose a mattress smaller than a queen-size. Why? You can avoid being disturbed by your partner tossing and turning. Take into consideration your height, weight and build. As a rule of thumb, your bed should also be 10 to 15cm longer than the taller partner. If you’re over 1.8m tall, consider a mattress that’s longer than the standard. And the heavier you weigh, the firmer the tension you’ll need.