It is sensible to make sure you have everything ready for your puppy before you bring him home.  If at all possible have someone around most of the time for the first few days to help settle him in and be there for when he is awake.  You should have sufficient food for the next few days and hopefully your breeder will have given you enough food to keep you going.  Also, have his bedding, crate, if you are using one, bowls and toys.  Remember to have plenty of newspapers for toilet training.

It is much easier if you are not alone in the car when bringing him home.  You need to be prepared for him to be car sick so make sure you take plenty of old towels, newspapers and kitchen roll with you. Hopefully he will not have been fed for some time before you travel.  It is best if there is someone to cuddle him all the way back  or to have a suitable size carrying cage or cardboard box for him to be in. Either way it is important that he is not loose in the car.