I would say pretty much the same as Jo , also if you dont have a bath , then a hot shower with you will help decongeste it .
My bosse's wife once told me to rub onion on their feet then put socks on them , but shes crazy , so ignore that
Unfortunatly thats one of the joys of kindy/creche/daycare , tho personally I think its a good thing for them to get colds, as unpleasent as it is for them , at least it builds up some kind of immunity .