Not an easy task when you have to study and understand their shape, with the tiny effects of light and shadows, for the best result. The color matters a lot too. Many reds turn out dull when dry and if the strawberry is completely red it's also a disadvantage. Choose those that have variety in color, light and dark... or invent some lighter zones.
Ad some Indian yellow to your red or use a Vermillon as you brightest red, for cast shadows any blue (light or dark) or grey mixed with a little of the strawberry's colors here and there will do.
The lighter the berries are the more luminous they will seem.