I keep a few on reels that I will use for practice casting on warm days but for the most part I pull them off the reels and clean and dress if needed. Then I gather each line into large (approx. 18 in. dia.) loops, secure with a twisted pipe cleaner, and drape over coat hangers to hang indoors. All of this I recognize as unnecessary but more of a ritual and insurance the lines will start the season clean. In fact sitting in a cold garage for the winter would be a lot better for them than spending the summer there due to the heat. I'll keep any lines I want to use in the winter on reels indoors so they at least start a practice session somewhat warm.