Hard to say with epsom salts as they are mangesium sulfate as opposed to magnesium chloride and sodium chloride.
When using sea salt or dead sea salt I would typically mix about a tea spoon to a large salad bowl of slightly cold water. Then I would dip my face in the water for as long as I could. After I was done I would simply rinse off and go on my way.
As noted in the article this worked really well at first, but after about a week results disappeared.
Cetaphil Restoraderm products worked really well for quite some time and currently I’ve made my own solution which I’ve been using for the past 2-3 months.
Hope that helps and let me know if you have any other questions.
Best of luck.