When you look at something from a completely different view, you will notice things you didn't before. Dangling cords, scent plug ins, shoes, and in our case yesterday... a 24 pack of water bottles. They are now strewn all over the landing and tiny pieces of plastic are everywhere...
One thing you need to make sure you are conscious of, is counters. I have a guilty habit of leaving stuff on the counter so it is "off the table." Thinking that the dogs can't get to it...well, just last week I walked into Baxter on the counter eating all the meat scraps from the previous night's dinner. I didn't realize he would jump from the table to the counter, I mean it is only 4 feet. But still! My counters are just loaded with stuff. So, make sure you keep anything that could be dangerous to your dog put up in cabinets so no emergencies happen.
Use gates. In our home, we have just one set of stairs leading to the basement. We have a gate at the top pf the stairs so that no dogs can down the stairs and get into trouble. Also, puppies should not go down stairs until they are at least 12 weeks old, larger breeders is recommended to wait even longer.
There are so many more things to look at when puppy-proofing your home. I highly recommend starting with these two!