Keep It Fresh
Freshly roasted coffee is a perishable product with delicate oils; extreme heat, cold, moisture, air, and even light have a negative impact on the aroma and flavor.
Store your coffee in a jar with a tight fitting lid kept out of direct sunlight. Keep it dry, that means don't put it in the fridge or freezer where it will collect moisture and can pick up unwanted flavors and aromas.
Whole beans will maintain their flavor the longest. Ground coffee begins to lose flavor immediately and is more prone to absorbing moisture.
Purchase only what you can use in a week or 2 for the best coffee. If stored properly, your coffee will maintain peak flavor for at least a week. After that you may notice an overall decline in aroma and the "cup quality".