Line a sieve over a larger bowl to catch the expressed liquid with either 3 layers of cheese cloth or a linen towel (See Note 2). Set aside.
In a bowl whisk together the yogurt and salt. Pour this into the lined sieve and carefully tie the loose cheese cloth or linen ends together.
Place the the bowl/sieve filled yogurt package in the refrigerator for 24 to 36 hours.
Discard the liquid and untie the package. The yogurt will be thick and slightly dry with a smooth creamy interior. Gently roll it out of the cheese cloth or linen and keep in a container that seals. Refrigerate for up to a week.
Notes
Traditionally I've read that 2 cups/450 grams of goat's milk yogurt is mixed with 2 cups/450 grams cow's milk yogurt. I love the texture and flavor from using all goats milk yogurt, if you can't find it, source from a Middle Eastern market, order online, or use all cow's milk yogurt.
When I first made this years ago I used 2 layers of cheesecloth and when I squeezed the yogurt after it had rested over night, I ripped the cheese cloth and the yogurt went everywhere. Triple or use 4 layers to be safe or a linen towel.