How does my little sister wear protective clothing and rubber boots?

Wear it directly outside normal clothes.

When you wear it, you should first unfold the protective clothing, put your feet into the trouser legs of the protective clothing, put on your coat, fasten your belt and put on long rubber shoes. Check the gas mask to see if it is tight. After confirmation, fasten the chest of protective clothing, buckle it into your pocket, put on protective gloves, put down your coat and fasten it.