I use a Campbell soup can because it is firm and the right size. I'd think that ice first thing would tighten your foot instead of loosen it. Maybe save the ice for later when it really hurts.
One suggesstion on soup cans, use a thick soup, like cream of mushroom. If you step down on it too hard you might pop the top off, and a thick soup is easier to clean up than a thin, runny soup. (Know that from experience
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