Heat Waves happen due to weather changes and pressure changes in the weather so there's no way to actually prevent heat waves.
I wish we could actually prevent or reduce heat waves from occurring however heat waves are not preventable because humans have no control over the weather.
So no matter how good you treat the earth the heat waves will still happen because no one can control the weather or weather patterns because the earth naturally does whatever it wants with the weather.
However doing your part to keep the air clean as much as possible and keep the earth in good shape for other people.
When a heat wave occurs you should stay inside an air conditioned space and keep hydrated by drinking plenty of water.
You should wait to go outside and do activities early in the morning or during the evening when the weather gets cooler to avoid heat related illnesses.