Sorry to see nobody answered your question yet.
One of the best things to do when you’re at home is get the shower all steamed up and get your child in the bathroom, because warm, moist air seems to work best to relax the vocal cords and break the stridor. A humidifier, not a hot vaporizer, but a cool mist humidifier also will help with getting the swelling down.
Call the doctor if your child:
Gets worse.
Has stridor constantly when resting.
Is less than 1 year old with stridor or a croupy cough.
Seems to not be able to catch his breath.
Cannot speak because breathing is so difficult.
Drools and cannot swallow his saliva.
Has trouble swallowing liquids and refuses to drink.
If your child has moderate or severe croup, they should be assessed promptly by the nearest emergency department. The time to go to hospital is if your child gets noisy breathing that doesn’t go away when they are resting. I would act quicker with a younger baby