These are the instructions from Dynasty for using the Tempura Batter Mix:
Pour vegetable oil for frying, at least 2' deep, in a large pot, deep frying pan or wok. Heat to 350°F. Pour 1-1/2 cups ice cold water into large mixing bowl.Sprinkle entire contents of the Tempura Batter Mix over water. With wire whisk or chopsticks stir in mix only until mix is moistened and large lumps disappear. Batter should be very lumpy. Drop in one ice cube. Do not stir batter after mixing.
To fry shrimp, hold one at a time by the tail and dip into batter. Drain off excess batter slightly and gently slide into hot oil. The same process should be done for any type of product you want to use with the batter (for example vegetables). Fry until golden brown. Remove from oil: drain briefly on paper towel. Keep warm. Skim pieces of cooked batter oil with wire strainer. Repeat with remaining ingredients.
As a note, once the bad of Tempura Batter Mix has been opened it should be stored in the refrigerator, tightly sealed, to retain freshness.