PU (polyurethane) rain gear can be machine washed on gentle, max 40℃. Use liquid detergent and no fabric softener. Wash raingear with the outside out, and avoid spin circle as it will lose the waterproofness faster. Dry the gear hanging , with the inside out.
Rain gear doesn’t need to be washed every day, it’s good to just wipe it down with a wet cloth.
If your rain gear is wet after all that fun time outside, make sure to let it hang free in an airy space to dry. PU fabric will break down if it lays folded while wet, for example in a bag over time.