Good racewalking technique includes an arm swing that takes your fist from your hip to mid-chest, with your elbow bent 90 degrees. Remember swinging your arms when walking as a kid?
Lift your toe as high as you can when your heel strikes the ground, and stride during walking exercise so your feet are almost one in front of the other. The high toe allows you to roll forward off your heel when power walking and racewalking, so you get a better push with your toes. Rotating your hips inward so your foot comes down in front of the other lengthens your walking stride.