Lioness, I found a good brand on Amazon, “Health and Wisdom” brand magnesium oil. I buy 1/2 gallon at a time although you can buy smaller amounts. The half gallon (64 ounces) lasts for weeks and weeks. I pour 4 ounces into an inch of warm water in a plastic container (bought at Target) that fits your feet. I soak my feet in it for 30 minutes every day or every other day. I use the solution 2-3 times and then toss it and prepare a new batch. It seems to help my occasional but sometimes painful leg cramps.