You only need simple gear for improving your race walking technique. It's important to avoid shoes or clothing that cause chafing. Like all sports, race walking requires specific accessories designed for the activity and the weather.
Choosing the right walking shoes is essential. There is less impact in race walking than running, but your shoes are the only contact you have with the ground so they have to absorb all the shock. They must be flexible, light and comfortable, and give good propulsion and grip.
For protection against cold weather, a long-sleeved insulating jersey is the walker's best ally. Add a thermal long-sleeved jacket for protection from the wind. A long pair of leggings will protect your thighs and keep you warm.
A pair of high anti-chafing socks protects the Achilles tendon. Choose a head band or buff rather than a beanie which doesn't let the heat escape. And don't forget gloves, vital for not having freezing fingertips. Race walking gear is similar to running gear.
To train in race walking in hot weather, wear shorts and a tank top. It's vital to apply anti-chafing cream to all the parts of your body which may be irritated to reduce inflammation.
Wear anti-UV sunglasses to protect your eyes from the wind and sun. To protect you from the heat, it is essential to wear a cap or visor. There are rarely shady areas on the bitumen, so you need to avoid your body getting too hot.
For staying hydrated when race walking, water-bottle belts are ideal. They have a little key pocket and you can also carry cereal bars or gels for snacks.
Comfort is very important. It's not expensive to start race walking... but don't forget the basic essentials!