How to socialize a puppy before they finish vaccines?

I will be getting a new puppy in December and I’d like some advice about how to get in safe socialization while the pup is still too young to have all their vaccines. I know those weeks before they can be fully vaccinated are crucial to introducing them to new experiences and socializing but I’m also a bit terrified of the pup picking up parvo from somewhere. I’ve read parvo horror stories on here about it being picked up on shoes or still alive in the soil in the yard for years and it’s making me anxious about taking the pup anywhere until they get their vaccines. But I also don’t want to set the puppy up for failure by neglecting their exposure to new people and places. What’s the balance of being safe and still getting in that crucial socialization?

Also I’ll be driving about 9 hours to pick up the pup and any advice on safe pit stops to let the pup potty and run off some energy would be greatly appreciated.