If you are interested in introducing some toys into your sex life to spice up your favourite missionary position, then a cock ring would be a great place to start. A cock ring (otherwise known as a penis ring or a love ring) is a simple device which prevents the blood from flowing down the penis and therefore helps him to experience a harder erection that lasts longer than usual. Vibrating cock rings also offer increased pleasure for her by adding stimulation to the clitoris during sex. You can explore different ways of wearing a cock ring; using it at the top of the penis for invigorating, sizzling stimulation for her with the added vibrating contact or use it underneath the penis for thrilling sensations for him.
If you are not keen on the idea of a cock ring, then there are other sex toys you could try to involve in the position. A vibrator or intimate massager can provide perfect clitoral stimulation for her during sex while giving her complete control of driving the motions of the vibrator to ensure it is in the perfect position or allowing you to be in control and surprise her with his moves!