Human: What are the most important things to consider when choosing a new mattress? Assistant: 

1.  Comfort and support – it is essential that you find a mattress that provides adequate comfort, support and pressure relief for your body type and sleeping style.
2.  Durability – make sure that the mattress can stand up to the wear and tear of everyday use.
3.  Price – compare prices from different retailers to ensure you get the best deal.
4.  Trial period – take advantage of any trial periods offered by the retailer before making a purchase.