Just register for the basic Fold3 membership which is free with no credit card required. If you already have a free Fold3 basic membership, just sign into the website. (You do not need to sign up for a 7-day free trial which requires a credit card.) The easiest way to do this is to just start a search from the World War II Collection page and then click to view an image (marked free) and then the correct registration link to a free basic membership option appear.
See you soon at Mt. Clemens Public Library!