There's nothing like warm weather to motivate you to clean the seldom-touched areas of your home. Hopefully that includes your mattress, as dead skin cells, body oils, sweat, bacteria and even mites will have built up over the past months without a deep clean. Need a new mattress? (Image credit: Future) If spring cleaning has exposed that your bed needs replacing, check out our guide to the best mattresses for all sleep styles But before you start spring cleaning your bed, remember that improper care risks voiding your mattress warranty. Sleep brands typically have guidelines on how to care for and clean your bed but not following proper care instructions can leave your pricey mattress unprotected by a warranty. 'Abnormal' cleaning methods to avoid include harsh chemicals that damage the mattress and excessive moisture that causes mold and mildew growth. What's more, these improper techniques can impact the comfort of your bed.…