With care, your stamps will last for years. Sunlight is an art stamp's worst enemy. It a very short time sunlight will dry out and crack the rubber, rendering it incapable of absorbing ink. Store your rubber stamps, image side down, in a cool, dark place.
To prolong their wear, clean your stamps after each impression. The easiest way is to moisten a paper towel with a very weak mixture of water and stamp cleaner or household window cleaner, then pat your stamp onto the paper towel to remove the ink. pat again on a clean, dry paper towel. Some stamp pros use commercial baby wipes instead. The cleansing agent is not only gentle to the rubber, but the moisturizers help keep it supple.
Till my next tip.... LOVE ONE ANOTHER! Make lots of art. Love you, mean it!