You may be best hanging off til spring and wait for the first warm day and let the sun beat down on it rolled out. It will go back into position but needs to be heated and stretched slowly to avoid rips and tears. It's the main reason I went to a tri-fold cover. I still think the snap styles look the best but the tri-folds are fast and no more hassles of shrinking.
Hot water! Either at the carwash, or at home! It will grow amazingly fast with Hot water! I used to use a local car wash, and literally spray hot water and button as you go. Never had problem's with it.