Hi Julie
If this is your first dog as an adult (as mine was), it's a bit of a minefield!
However, as I said in a previous thread, the best advice the breeder gave us was 'Get him out and about early'.
She made the point that far more dogs die through being sent to dogs homes because of behavioural problems, than puppies die through picking up diseases. Guide Dogs for the Blind let their puppies out really early (6 weeks) and we all know how good they are.
I had Barney out with me from 8 weeks. We'd have gentle trips on a bus to a cafe, and he met nice dogs of friends. A drive round in the car, and a short walk to the postoffice etc. Nothing over an hour, really, but he got used to meeting people and dogs and getting used to his surroundings (noisy London).
Also - handle him, too. Hold his paws, fold back his ears, touch his mouth so he gets used to it. It will pay dividends when you have to take him to a vet or take something nasty out of his mouth on a walk.
Every dog I've met that was kept indoors until the second jabs has been yappy.
Let me know how it goes!
Nick