How To Vaccinate 6 week old Labs?

While growing I had known of many people who vaccinated their own animals. They would go to a livestock supply store and purchase their own vaccinations. I now have 8 puppies and am wondering if this is something I can do myself. My mamma dog was in the vet alot throughout this whole event. As well as babies went to vet for early check up. I dread the idea of going back to the vet to spend another $300. I know they deserve the best and want to give it to them, but if this is something I can do I would love to do it myself. Anyone with information and advice would be appreciated.