I would buy ice packs that have an outer covering already in place. That is what I did, but unfortunately directly applied them to my skin for too long. You can of course always use a 'buffer' material such as a hand towel, washcloth, or even a dish towel type material. The important part I found was just not to apply it for too long and again, not directly on my skin for long periods. "Official" ice packs that you purchase have specific instructions, and that can be particularly helpful. Also, many official ice packs have wrap around Velcro strapping that holds them in place. Physical or occupational therapists are great resources as well for any condition - how long should I keep an ice pack on and how many times per day is optimal? Those are great questions to ask.