Suggestions on how to start

First interview all living relatives. Remember that not all the information you get from these interviews will be correct, people's memories are not perfect and some like to improve on an interesting story, so use public records to verify. These also are not always correct the information still comes from people and is sometimes misunderstood, written poorly, misspelled and put in the wrong place. But if 2 sources agree it's most likely correct. Once you have the information on your parents, grandparents and as far back as living relatives can take you then you are ready to start researching.