How can I teach DS to blow his nose?

[Niecie]

DS2 has a bad tickly cough and the beginnings of a runny nose. He would cough less, I am sure, if he could blow his nose but he can't seem to get the hang of blowing down his nose. He can sniff, which naturally makes the cough worse, but he can't seem to do it the other way.

Any ideas or tricks? (DS1 seemed to know what to do automatically so no past experience).

DS2 is 4 and very capable in a lot of ways but he can't get this at all.

Sorry about the delay in posting - we have had internet problems today and keep losing the connection

try asking him to close his mouth first, take a deep breath and blow without opening his mouth. Use bubbles to blow at, as this can make him realise when he does it right.

Thanks tori32 - I have tried getting him to blow out candles with his nose but haven't asked him to keep his mouth shut - that might be the key. Will also have a go with bubbles.