Seasoning cookware seals the surface of the metal, which would otherwise corrode, particularly with high-acid food. Your aluminum cookware is not pure aluminum, but aluminum oxide. The aluminum surface is oxidized in an electro-chemical bath, creating a surface harder than stainless steel. This hard surface is anodized aluminum, which prevents rust, prevents food from sticking and creates a barrier against metal leaching into the food. Although the aluminum is already sealed, properly seasoning your anodized cookware ensures better cooking results.
Wash your new cookware with mild dish soap in hot water to remove debris and packing oils. Rinse thoroughly, and dry with a paper towel or cloth.
Put cookware over high heat. Pour some cooking oil into the cookware, and spread it around with a new clean sponge, covering the interior surface up to the rim.
Remove cookware from heat when the oil begins to smoke, and let it cool completely.
Wipe off any excess oil with a kitchen cloth or paper towel.
Hand wash with warm water after each use. Re-season the cookware after washing if you must use soap to remove stubborn food.