Washing your rain gear including your rain jacket, pants, gloves, and sock-like boots is nothing complicated. Such items should come with instructions to help you keep your motorcycle gear clean and in good shape. They can usually be washed in the washing machine as long as you go for a gentle cycle that uses warm water.
Make sure you use a cleaning solution that was specifically formulated for such type of garment. You can also clean your one-piece rain suit and other such items with a spray-on treatment. There is a variety of such quality products available for sale since they are effective and easy to use.